JP3986396B2 - Simultaneous recording / reproducing method and information recording / reproducing apparatus - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an information recording medium capable of simultaneously recording / reproducing a plurality of real-time data, a method for simultaneous recording / reproducing, and an information recording / reproducing apparatus.
[0002]
[Prior art]
There is a hard disk as an information recording medium having a sector structure. In recent years, capacity and multimedia have been increasing, and applications from personal computers to consumer devices are progressing.
[0003]
Hereinafter, simultaneous recording / playback with a conventional hard disk will be described with reference to the drawings. In the hard disk, the size of the recording / reproducing area is fixed in advance to a unit larger than the sector, and access is performed in a fixed block unit.
[0004]
FIG. 2 shows a simultaneous recording / reproducing model for simultaneously recording / reproducing two real-time data. The simultaneous recording / reproducing model includes a pickup 74 for recording / reproducing real-time data with respect to an information recording medium, an encoder 70 for encoding first real-time data, and a pickup 74 for encoding first real-time data. The recording buffer 72 temporarily stored before recording, the reproduction buffer 73 temporarily holding the second real-time data reproduced by the pickup 74, and the second real-time data transferred from the reproduction buffer 73. And a decoder 71 for decoding data.
[0005]
FIG. 30 shows an example in which two real-time data are recorded and reproduced simultaneously using the recording buffer 72 and the reproduction buffer 73 while ensuring continuity. In this example, the second real-time data recorded in the areas 83 and 85 on the information recording medium is reproduced while the first real-time data is recorded in the areas 81 and 84 on the information recording medium.
[0006]
In FIG. 30, A81, A82, and A83 indicate an operation (access operation) of moving between areas that the pickup 74 should access. The time required for the access operations A81, A82, and A83 is the time required for the pickup 74 to access between the innermost area and the outermost area of the information recording medium (that is, the maximum time) It is assumed that the access time is Ta). It is assumed that the data transfer rate between the pickup 74 and the recording buffer 72 and the data transfer rate between the pickup 74 and the reproduction buffer 73 are constant Vt. It is assumed that the data transfer rate between the encoder 70 and the recording buffer 72 and the data transfer rate between the decoder 71 and the reproduction buffer 73 are constant Vd. Vd is the maximum value of the variable rate when the data to be recorded / reproduced is compressed at the variable rate.
[0007]
In the recording operation W81, all data accumulated in the recording buffer 72 is recorded in the area 81. Thereafter, data is stored in the recording buffer 72 during the access operation A81, the reproduction operation R81, and the access operation A82. In the recording operation W82, all the data stored in the recording buffer 72 is recorded in the area 84. Thereafter, data is stored in the recording buffer 72 during the access operation A83, the reproduction operation R82, and the next access operation (not shown).
[0008]
On the other hand, the data accumulated in the reproduction buffer 73 is consumed during the recording operation W81 and the access operation A81, and the data is accumulated in the reproduction buffer 73 in the reproduction operation R81. Thereafter, the data accumulated in the reproduction buffer 73 is consumed during the access operation A82, the recording operation W82, and the access operation A83, and the data is accumulated in the reproduction buffer 73 in the reproduction operation R82.
[0009]
Thus, when the transfer rate of data to be recorded and reproduced is constant, the data amount in the recording buffer 72 is balanced between the recording state and the non-recording state, and the data amount in the reproduction buffer 73 is also reproduced. Balanced between state and non-playback state. Further, since the recording of the first real-time data and the reproduction of the second real-time data are alternately performed, the recording and reproduction of the two real-time data can be continuously performed.
[0010]
The example shown in FIG. 30 also serves as a condition indicating the minimum size of an area where data can be recorded and reproduced. That is, since it is not possible to define where the recording / reproducing area exists on the disc, the access between the recording area and the reproducing area is considered as the maximum access time including waiting for rotation.
[0011]
FIG. 31 is a diagram showing changes in the amount of data in the recording buffer 72 and the reproduction buffer 73 when variable-rate data is recorded and reproduced. At the end of the recording operation W91, the access operation A91, the reproduction operation R91, and the access operation A92, if data larger than the size of the recording area is not stored in the recording buffer 72, the recording data is halfway if the recording rate is low Is not enough to cause rotation waiting and recording time increases. In this case, an access operation A93 for accessing the next area where real-time data is recorded is performed, and a reproduction operation R92 is performed. As described above, when data is recorded for each fixed-size block and accessed in units of fixed blocks, the size of the fixed block is equal to the amount of data stored in two access times and the playback time of one playback area. The size of the buffer memory required for the recording buffer 72 is obtained by adding. Conversely, the reproduction buffer 73 also requires a buffer memory having the same size as the recording buffer 72.
[0012]
In the case of a hard disk, since the data transfer capability is high, the size of the fixed block can be reduced and the size of the buffer memory can also be reduced.
[0013]
[Problems to be solved by the invention]
However, when simultaneous recording / playback of the above-described method is applied to an optical disc, there is a problem that a large buffer memory is required because the optical disc has a low data transfer rate and a long access time. In addition, in order to perform simultaneous recording / playback even with a disc recorded by another device, there is a problem in that it is necessary to stably perform simultaneous recording / playback while ensuring compatibility.
[0014]
[Means for Solving the Problems]
  The method of the present invention comprises:A method of simultaneously recording and reproducing a plurality of real-time data on an information recording medium according to a simultaneous recording / reproducing model, wherein the simultaneous recording / reproducing model includes a pickup P for accessing an area on the information recording medium, and real-time data Di. An encoding module EMi, a recording buffer WBi for storing encoded real-time data Di, a reproduction buffer RBj for storing real-time data Dj read from the information recording medium, and a reproduction buffer RBj And a decoding module DMj for decoding the real-time data Dj stored in the information recording medium, wherein the method searches for an unallocated area in the volume space on the information recording medium, and at least one unrecorded area in the volume space. Allocation area is allocated as area Ai for recording real-time data Di The first step, the second step of executing the recording operation Wi for recording the real-time data Di accumulated in the recording buffer WBi in the area Ai, and the real-time data Dj are read from the area Aj in which the real-time data Dj is recorded During the third step of executing the reproducing operation Rj and the recording operation Wi, it is determined whether or not the recording buffer WBi is empty. If it is determined that the recording buffer WBi is empty, When the operation Wi is switched to another recording operation or the reproduction operation Rj, and it is determined that the recording buffer WBi is not empty, during the fourth step of continuing the recording operation Wi and the reproduction operation Rj, It is determined whether or not the reproduction buffer RBj is full. If it is determined that the reproduction buffer RBj is full, the reproduction buffer RBj is reproduced. The real-time data to be recorded includes the fifth step of switching the operation Rj to another reproduction operation or recording operation Wi and continuing the reproduction operation Rj when it is determined that the reproduction buffer RBj is not full. At least one of Di and the real-time data Dj to be reproduced includes data encoded at a variable rate, and each of at least one area allocated as the area Ai has the access operation at most once. It is configured to satisfy the condition that the recording buffer WBi can be made empty by at most two recording operations, and each of at least one area allocated as the area Aj is accessed at most once. It is said that the playback buffer RBj can be full with the operation and at most two playback operations. Where i is an arbitrary integer from 1 to m, j is an arbitrary integer from m + 1 to n, and m is 1 or more that satisfies m <n. An arbitrary integer, n is an arbitrary integer of 2 or more indicating the number of a plurality of real-time data to be simultaneously recorded and reproduced, and the minimum size of the area allocated as the area Ai is the data of the real-time data Di When the rate is the maximum, the amount of data in the recording buffer WBi consumed when the real-time data Di recording operation consisting of one access operation and two recording operations is executed in the second to fifth steps. And the amount of data stored in the recording buffer WBi when the real-time data Dj reproduction operation including other access operations and reproduction operations is executed. And butterflies.
[0015]
  When the data rate of the real-time data Di is maximum, the minimum size of the area allocated as the area Ai is a real-time value that includes one access operation and two recording operations in the second to fifth steps. Data amount of recording buffer WBi consumed when data Di recording operation is executed, and data stored in recording buffer WBi when real time data Dj reproducing operation including other access operation and reproducing operation is executed The amount may be determined to be equal.
[0016]
  When simultaneously recording and reproducing two real-time data, the second to fifth steps are the first recording operation, the first access operation, the second recording operation, the second access operation, the first reproduction operation, and the third access operation. The second reproduction operation and the fourth access operation are executed in this order, and the real-time data Di recording operation is composed of the first recording operation, the first access operation, and the second recording operation, and the real-time data Dj reproduction operation is the first operation It may be composed of a two-access operation, a first reproduction operation, a third access operation, a second reproduction operation, and a fourth access operation..
[0017]
  Each of the at least one region allocated as the region Ai has a size equal to or larger than Y, and each of the at least one region allocated as the region Aj has a size equal to or larger than Y, Here, Y = 2 × n × Ta × Vd × Vt ÷ (Vt−n × Vd), where Ta is a distance between a region where the pickup P is on the innermost periphery and a region on the outermost periphery of the information recording medium. The access time required for access is indicated, Vt indicates the data transfer rate between the pickup P and the recording buffer WBi and the data transfer rate between the pickup P and the reproduction buffer RBj, and Vd indicates all i , J, the data transfer rate between the encoding module EMi and the recording buffer WBi and the data transfer between the decoding module DMj and the reproduction buffer RBj Shows the over door, may be.
[0018]
  Each of the at least one region allocated as the region Ai has a size equal to or greater than Yi, and each of the at least one region allocated as the region Aj has a size equal to or greater than Yj, Here, Yi = (2 * n * Ta * Vt * Vdi) / {Vt- (Vd1 + Vd2 + ... + Vdn)}, Yj = (2 * n * Ta * Vt * Vdj) / {Vt- (Vd1 + Vd2 +) + Vdn)}, Ta represents an access time required for the pickup P to access between the innermost area and the outermost area of the information recording medium, and Vt represents the recording with the pickup P. Indicates the data transfer rate between the buffer WBi and the data transfer rate between the pickup P and the reproduction buffer RBj, Vdi is the encoding module EMi and the recording buffer Indicates the data transfer rate between the WBi, VDJ indicates the data transfer rate between the decoding module DMj the reproduction buffer RBj, may be so.
[0019]
  The area Ai and the area Aj may be provided in an area with a radius of 38 mm to 58 mm of the information recording medium for all i and j.
[0020]
  The information recording / reproducing apparatus of the present invention is an information recording / reproducing apparatus for simultaneously recording / reproducing a plurality of real-time data on an information recording medium in accordance with a simultaneous recording / reproducing model, Pickup P for accessing the area, encoding module EMi for encoding the real-time data Di, recording buffer WBi for storing the encoded real-time data Di, and real-time data read from the information recording medium A playback buffer RBj for storing Dj, and a decoding module DMj for decoding the real-time data Dj stored in the playback buffer RBj, wherein the information recording / playback apparatus is an unrecorded volume in the volume space on the information recording medium. Search for the allocated area and reset at least one unallocated area in the volume space. The first means for allocating the real time data Di as the area Ai for recording, the second means for executing the recording operation Wi for recording the real time data Di stored in the recording buffer WBi in the area Ai, and the real time data Dj The third means for executing the reproduction operation Rj for reading out the real-time data Dj from the recorded area Aj, and whether or not the recording buffer WBi is empty while executing the recording operation Wi, the recording buffer WBi If it is determined that the recording operation Wi is empty, the recording operation Wi is switched to another recording operation Wi or the reproduction operation Rj. If it is determined that the recording buffer WBi is not empty, the fourth means for continuing the recording operation Wi. During the reproduction operation Rj, it is determined whether or not the reproduction buffer RBj is full, and the reproduction buffer RB Is determined to be full, the reproduction operation Rj is switched to another reproduction operation Rj or the recording operation Wi. If it is determined that the reproduction buffer RBj is not full, the fifth reproduction operation Rj is continued. And at least one of the recorded real-time data and the reproduced real-time data includes data encoded at a variable rate, and each of the at least one area allocated as the area Ai is Each of the at least one area allocated as the area Aj is configured to satisfy the condition that the recording buffer WBi can be made empty by at most one access operation and at most two recording operations. Fills the playback buffer RBj with at most one access operation and at most two playback operations. Where i is any integer between 1 and m, j is any integer between m + 1 and n, and m is m <n. Any integer equal to or greater than 1 is satisfied, n is an integer equal to or greater than 2 indicating the number of real-time data to be simultaneously recorded and played back, and the minimum size of the area allocated as the area Ai is the real-time When the data rate of the data Di is maximum, the recording buffer WBi consumed when a real-time data Di recording operation consisting of one access operation and two recording operations is executed in the second to fifth means. And the amount of data stored in the recording buffer WBi when the real-time data Dj playback operation including other access operations and playback operations is executed. And wherein the be fit.
[0021]
  When the data rate of the real-time data Di is the maximum, the minimum size of the area allocated as the area Ai is a real-time value comprising one access operation and two recording operations in the second to fifth means. Data amount of recording buffer WBi consumed when data Di recording operation is executed, and data stored in recording buffer WBi when real time data Dj reproducing operation including other access operation and reproducing operation is executed The quantity may be determined to be equal to each other..
[0022]
  In the case of simultaneously recording and reproducing two real-time data, the second to fifth means are the first recording operation, the first access operation, the second recording operation, the second access operation, the first reproduction operation, and the third access operation. , The second reproduction operation and the fourth access operation are executed in order, the real-time data Di recording operation is composed of the first recording operation, the first access operation, and the second recording operation, and the real-time data Dj reproduction operation is the first operation You may make it comprise 2 access operation | movement, 1st reproduction | regeneration operation | movement, 3rd access operation | movement, 2nd reproduction | regeneration operation | movement, and 4th access operation | movement.
[0023]
  Each of the at least one region allocated as the region Ai has a size equal to or larger than Y, and each of the at least one region allocated as the region Aj has a size equal to or larger than Y, Here, Y = 2 × n × Ta × Vd × Vt ÷ (Vt−n × Vd), where Ta is a distance between a region where the pickup P is on the innermost periphery and a region on the outermost periphery of the information recording medium. The access time required for access is indicated, Vt indicates the data transfer rate between the pickup P and the recording buffer WBi and the data transfer rate between the pickup P and the reproduction buffer RBj, and Vd indicates all i , J, the data transfer rate between the encoding module EMi and the recording buffer WBi and the data transfer between the decoding module DMj and the reproduction buffer RBj Shows the over door, may be as in.
[0024]
  Each of the at least one region allocated as the region Ai has a size equal to or greater than Yi, and each of the at least one region allocated as the region Aj has a size equal to or greater than Yj, Here, Yi = (2 * n * Ta * Vt * Vdi) / {Vt- (Vd1 + Vd2 + ... + Vdn)}, Yj = (2 * n * Ta * Vt * Vdj) / {Vt- (Vd1 + Vd2 +) + Vdn)}, Ta represents an access time required for the pickup P to access between the innermost area and the outermost area of the information recording medium, and Vt represents the recording with the pickup P. Indicates the data transfer rate between the buffer WBi and the data transfer rate between the pickup P and the reproduction buffer RBj, Vdi is the encoding module EMi and the recording buffer Indicates the data transfer rate between the WBi, VDJ indicates the data transfer rate between the decoding module DMj the reproduction buffer RBj, may be so.
[0040]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0041]
(Embodiment 1)
A method for simultaneously recording and reproducing a plurality of real-time data according to the simultaneous recording and reproduction model will be described below. The simultaneous recording / reproducing model is the same as the simultaneous recording / reproducing model shown in FIG. 2 in that it has two buffers, a recording buffer 72 and a reproduction buffer 73. Here, the real-time data refers to data including at least one of video data and audio data. An information recording medium refers to any type of recording medium such as an optical disk.
[0042]
FIG. 1 shows the transition of the data amount in the recording buffer 72 and the reproduction buffer 73 of the simultaneous recording / reproducing model when the real-time data A and B are simultaneously recorded / reproduced.
[0043]
In the example shown in FIG. 1, real-time data A is recorded in areas 5, 6, 7, and 8 on the information recording medium while real-time data A is recorded in areas 1, 2, 3, and 4 on the information recording medium. Play data B. Here, areas 1 to 4 are areas allocated as areas for recording real-time data A, and areas 5 to 8 are areas allocated as areas for recording real-time data B.
[0044]
In FIG. 1, A1 to A7 indicate operations (access operations) in which the pickup 74 moves between areas to be accessed. The time required for the access operations A1 to A7 is the time required for the pickup 74 to access between the innermost area and the outermost area of the information recording medium (that is, the maximum access time Ta). ). The data transfer rate between the recording buffer 72, the reproduction buffer 73, and the pickup 74 is assumed to be a constant Vt. It is assumed that the data transfer rate between the encoder 70 and the recording buffer 72 and the data transfer rate between the decoder 71 and the reproduction buffer 73 are constant Vd. Vd is the maximum value of the variable rate when the data to be recorded / reproduced is compressed at the variable rate.
[0045]
In the recording operation W1, the real-time data A accumulated in the recording buffer 72 is recorded in the area 1. Since the recording buffer 72 is not empty at the end of the area 1, switching from the recording operation of the real-time data A to the reproducing operation of the real-time data B does not occur. After the access operation A1, the real-time data A stored in the recording buffer 72 is recorded in the area 2 in the recording operation W2.
[0046]
While the recording operation W2 is being executed, the recording buffer 72 becomes empty. As a result, switching from the recording operation of the real-time data A to the reproducing operation of the real-time data B occurs (access operation A2).
[0047]
In the reproduction operation R 1, the real-time data B is read from the area 5 and accumulated in the reproduction buffer 73. Since the reproduction buffer 73 is not full at the end of the area 5, switching from the reproduction operation of the real-time data B to the recording operation of the real-time data A does not occur. After the access operation A3, the real time data B is read from the area 6 and stored in the reproduction buffer 73 in the reproduction operation R2.
[0048]
While the reproduction operation R2 is being performed, the reproduction buffer 73 becomes full. As a result, switching from the reproduction operation of the real-time data B to the recording operation of the real-time data A occurs (access operation A4).
[0049]
As described above, the simultaneous recording / reproducing method of the present invention has the condition that the recording buffer 72 can be empty by at most one access operation and at most two recording operations, and at most one time. The reproduction buffer 73 is designed to satisfy both a condition that the reproduction buffer 73 can be full by an access operation and at most two reproduction operations. That is, the simultaneous recording / reproducing condition is to satisfy both of these two conditions. As a result, the real-time data A was recorded on the information recording medium without causing the recording buffer 72 and the reproduction buffer 73 to overflow and without causing the recording buffer 72 and the reproduction buffer 73 to underflow. It is possible to ensure that the real-time data B is reproduced.
[0050]
For example, each of at least one recording area allocated as an area for recording real-time data A has a size equal to or larger than Y, and at least one reproduction area allocated as an area for recording real-time data B Since each has a size equal to or larger than Y, the simultaneous recording / playback condition can be satisfied. Therefore, in order to satisfy the simultaneous recording / reproducing condition, at least one unallocated area having a size equal to or larger than Y is searched, and at least one recording area thus searched is used as an area for recording real-time data A. You just have to assign it. The same applies to the area where the real-time data B is recorded.
[0051]
In the example shown in FIG. 1, the simultaneous recording / reproducing conditions can be satisfied because each of the areas 1 to 4 has a size of Y or larger and each of the areas 5 to 8 has a size of Y or larger.
[0052]
Here, the minimum size Y of the recording area and the reproduction area and the buffer size B required for the recording buffer 72 and the reproduction buffer 73 are obtained according to the following equations.
[0053]
Y = 4 × Ta × Vd × Vt ÷ (Vt−2 × Vd)
B = (4 × Ta + Y ÷ Vt) × Vd
The expression of the minimum size Y of the recording area and the reproduction area is derived as follows.
[0054]
In the recording operation of the real-time data A, the data in the recording buffer 72 is consumed at Vt−Vd, and in the access operation and the reproducing operation of the real-time data B, the data in the recording buffer 72 is accumulated at Vd. The amount of data in the recording buffer 72 consumed during the recording operation W1, the access operation A1, and the recording operation W2 is accumulated between the access operation A2, the reproduction operation R1, the access operation A3, the reproduction operation R2, and the access operation A4. The amount of data in the recording buffer 72 is equal. Therefore, when recording and reproducing two pieces of real-time data simultaneously, the following equation is established.
[0055]
Y ÷ Vt × (Vt−Vd) −Ta × Vd = (3 × Ta + Y ÷ Vt) × Vd
By transforming this formula, a formula for the minimum size Y of the recording area and the reproduction area is obtained.
[0056]
When the number of real-time data to be recorded / reproduced is n (n is an arbitrary integer of 2 or more), m encoders, m recording buffers, (n A simultaneous recording / playback model is used which includes -m) decoders and (nm) playback buffers. m is an arbitrary integer of 1 or more that satisfies m <n. In this case, since the number of access operations is proportional to the number of real-time data to be simultaneously recorded / reproduced, Y ÷ Vt × (Vt−Vd) −Ta × Vd = ((2 × n−1) × Ta + (n−1) ) × Y ÷ Vt) × Vd. Therefore, when the number of real-time data to be simultaneously recorded / reproduced is n, the minimum size Y of the recording area and the reproduction area and the size B required for the recording buffer and the reproduction buffer are obtained according to the following equations.
[0057]
Y = 2 × n × Ta × Vd × Vt ÷ (Vt−n × Vd)
B = (2 × n × Ta + (n−1) × Y / Vt) × Vd
Note that the number of real-time data to be recorded and the number of real-time data to be reproduced may be different. As described above, the recording operation may be switched to another recording operation, or may be switched to the reproduction operation. Similarly, the playback operation may be switched to another playback operation or may be switched to a recording operation. If the transfer rate of data to be recorded or reproduced is the maximum rate, it is obvious that n real-time data may be recorded or reproduced, and there is no limitation on the combination thereof.
[0058]
As described above, when two real-time data are recorded and reproduced simultaneously, one of the differences from the conventional example is that the number of access operations is four. In the present invention, the access operation is at least assigned as a region for recording the real-time data A (or real-time data B) when switching between the real-time data A recording operation and the real-time data B reproduction operation. Occurs when accessing one from one of the areas. Therefore, in the present invention, after the recording buffer 72 becomes full and before the recording buffer 72 becomes full (or after the reproduction buffer 73 becomes empty and before the reproduction buffer 73 becomes empty). It defines a model that can be accessed four times. This makes it possible to dynamically switch between recording and playback operations according to changes in the amount of data in the recording buffer and playback buffer, and stable control of changes in the amount of data in the recording buffer and playback buffer. It becomes possible to do. That is, when the amount of data in the recording buffer 72 becomes almost full, the data amount in the recording buffer 72 is reduced by immediately switching from the reproducing operation of the real-time data B to the recording operation of the real-time data A. be able to. Further, when the data amount in the reproduction buffer 73 becomes nearly empty, the data amount in the reproduction buffer 73 is increased by immediately switching the recording operation of the real time data A to the reproduction operation of the real time data B. be able to.
[0059]
FIG. 3 shows an example of an area arrangement of an information recording medium (optical disc) on which a file managed by a volume file structure defined by the ECMA167 standard is recorded.
[0060]
3, W1 to W4 indicate the recording operation described with reference to FIG. 1, R1 to R4 indicate the reproduction operation described with reference to FIG. 1, and A1 to A7 have been described with reference to FIG. Indicates an access operation.
[0061]
The upper side of FIG. 3 shows the inner peripheral side of the optical disc, and the lower side of FIG. 3 shows the outer peripheral side of the optical disc. A volume structure area 11 and a file structure area 12 are allocated to the volume space. The file structure area 12 includes a space bitmap 21 in which unused areas in the volume space are registered as unallocated areas in units of sectors, and a data structure corresponding to the directory structure shown in FIG. An entry 22, a FILE-A file identification descriptor 23, a FILE-B file identification descriptor 24, a FILE-A file entry 25, and a FILE-B file entry 26).
[0062]
In the ECMA167 standard, an area in which file data is recorded is called an extent, and extent position information is registered in a file entry. A file identification descriptor is recorded in the file structure area 12 for each file under the directory.
[0063]
An area where real-time data is recorded is called a real-time extent in order to distinguish it from an area where general data is recorded.
[0064]
In the example shown in FIG. 3, recording areas 13, 14, and 15 on the inner circumference side of the optical disc are allocated as areas for recording FILE-A real-time data, and FILE-B real-time data is recorded. Reproduction areas 16, 17, and 18 are assigned as areas. The recording area 15 and the reproduction area 16 have an access time required to access between these areas, and an access time required to access an outermost area from an innermost area of the optical disc. It is assumed that they are separated by as much as
[0065]
Each of the recording areas 13 to 15 has a size equal to or larger than the minimum size Y of the recording area so as to satisfy the above-described simultaneous recording / reproducing condition. Each of the playback areas 16 to 18 has a size equal to or larger than the minimum size Y of the playback area so as to satisfy the above-described simultaneous recording / playing condition. Thereby, for example, even if the area where the real-time data is actually recorded is a part of the recording area, the real-time data can be recorded in the next recording area after the access operation. Real-time data can be recorded in an area of size Y or larger. Further, under the simultaneous recording / playback condition described with reference to FIG. 1, the time required for access operation (access time) is the access necessary for accessing the outermost area from the innermost area of the optical disc. Since time is used, simultaneous recording / playback can be guaranteed regardless of where the recording area and the reproduction area are arranged on the optical disc.
[0066]
FIG. 4 shows changes in the amount of data in the recording buffer 72 and the reproduction buffer 73.
[0067]
Hereinafter, with reference to FIG. 4, the relationship between the change in the data rate of the data to be recorded and reproduced and the transition of the data amount in the recording buffer and the reproduction buffer will be described.
[0068]
Assume that recording areas 30 and 31 are allocated as areas for recording real-time data A, and reproduction areas 35 and 36 are allocated as areas where real-time data B is recorded. The recording area 31 includes an area 32, an area 33, and an area 34. The reproduction area 36 includes an area 37, an area 38, and an area 39.
[0069]
In the recording operation of the real-time data A, when the rate of data transferred to the recording buffer 72 is the maximum rate, the recording buffer 72 is recorded at time t24 as a result of performing the recording operation W11, the access operation A11, and the recording operation W13. Become empty. When the rate of data transferred to the recording buffer 72 is smaller than the maximum rate, the amount of data transferred from the encoder 70 to the recording buffer 72 is small, so that the recording operation W11, the access operation A11, and the recording operation W12 are performed. The recording buffer 72 becomes empty at time t23 earlier than time t24. That is, when the data transfer rate from the encoder 70 to the recording buffer 72 is small, the recording buffer 72 becomes empty at an early time. When the recording operation of the real-time data A is switched to the reproducing operation of the real-time data B at time t23, the time required for switching to the next recording operation is the time required for three access operations and two reproductions. The recording buffer 72 does not overflow because it is less than the sum of the time required for the two playback operations for reproducing data from the area. Further, in the next recording operation, even if data of the maximum rate has to be recorded, the data can be recorded in an area having a size of Y obtained from the simultaneous recording / reproducing conditions.
[0070]
On the other hand, in the reproduction operation of the real-time data B, if the rate of data transferred from the reproduction buffer 73 is the maximum rate, the data can be read from the Y size area by one reproduction operation. When the rate of data transferred from the reproduction buffer 73 is the maximum rate, the reproduction buffer 73 becomes full at time t29 as a result of performing the reproduction operation R11, the access operation A14, and the reproduction operation R13. When the rate of data transferred from the reproduction buffer 73 is smaller than the maximum rate, the amount of data transferred from the reproduction buffer 73 to the decoder 71 is small, and the result of performing the reproduction operation R11, the access operation A14, and the reproduction operation R12. The playback buffer 73 becomes full at time t28 earlier than time t29. That is, when the data transfer rate from the reproduction buffer 73 to the decoder 71 is small, the reproduction buffer 73 becomes full at an early time. If the playback operation of the real-time data B is switched to the recording operation of the real-time data A at time t28, the time required for switching to the next playback operation is the time required for the three access operations and two recordings The reproduction buffer 73 does not underflow because it is less than the sum of the time required for the two recording operations for recording data in the area. In the next reproduction operation, even if it is necessary to reproduce the data at the maximum rate, the data can be reproduced from the area having the size of Y obtained from the simultaneous recording / reproducing conditions.
[0071]
Next, the information recording / reproducing apparatus according to the embodiment of the present invention and the simultaneous recording / reproducing method will be described with reference to FIG. 3, FIG. 5, and FIG.
[0072]
FIG. 5 shows the configuration of the information recording / reproducing apparatus according to the embodiment of the present invention.
[0073]
The information recording / reproducing apparatus includes a system control unit 501, an I / O bus 521, an optical disk drive 531, an input unit 532 for instructing designation of a recording mode and start of simultaneous recording / reproducing, and a tuner 535 for receiving a TV broadcast. , An encoder 533 for encoding the audio video signal selected by the tuner 535, a decoder 534 for decoding the audio video data, and a TV 536 for reproducing the audio video signal.
[0074]
The system control unit 501 is realized by, for example, a microcomputer and a memory. Each unit included in the system control unit 501 is realized by, for example, a microcomputer executing various programs. Each memory included in the system control unit 501 is realized, for example, by properly using a single memory area for each application.
[0075]
The recording / reproducing switching means 502 switches between a recording operation and a reproducing operation while checking the amount of data in the buffer memory. The unallocated area search unit 503 searches an area that satisfies the simultaneous recording / reproducing condition from the unallocated areas in the volume space. The file structure processing unit 504 reads data from the file structure area 12 and analyzes the file structure. The data recording unit 505 instructs the optical disc drive 531 to record data. The data reproducing unit 506 instructs the optical disk drive 531 to reproduce data.
[0076]
The allocated area memory 507 temporarily holds the position information of the recordable area searched by the unallocated area searching unit 503. The file structure memory 508 is for temporarily holding data read from the file structure area 12 on the buffer memory. The bitmap memory 509 is for reducing access to the disk by holding data read from the space bitmap 21. The recording buffer memory 510 and the reproduction buffer memory 511 correspond to the recording buffer 72 and the reproduction buffer 73 of the simultaneous recording / reproducing model, respectively, and have a buffer memory larger than the size calculated under the simultaneous recording / reproducing conditions.
[0077]
FIG. 6 shows the procedure of the simultaneous recording / reproducing method. Such a method can be stored in a memory in the system control unit 501 in the form of a program, for example. Such a program can be executed by a microcomputer in the system control unit 501, for example.
[0078]
The user uses the input unit 532 to input a simultaneous recording instruction to the information recording / reproducing apparatus. In accordance with the simultaneous recording instruction, the minimum size Y of the recording area corresponding to the maximum data rate of the data to be recorded is determined. The method for obtaining the minimum size Y of the recording area is as described with reference to FIG. 1 (Y = 4 × Ta × Vd × Vt ÷ (Vt−2 × Vd)). When a specific program such as a movie is recorded, the user sets a recording time. In this way, the recording parameter is determined (step S601).
[0079]
For each real-time data to be recorded, the unallocated area search means 503 uses an unallocated area having a size equal to or larger than the minimum size Y of the recording area obtained in step S601 as data stored in the bitmap memory 509. And search. When the user specifies the recording time, the unallocated area in the volume space is searched until the total size of the unallocated area is equal to or greater than the product of the maximum rate and the recording time, and at least one unallocated area in the volume space is searched. The allocation area is allocated as an area for recording real-time data (step S602). Therefore, each of at least one area allocated as an area for recording real-time data has a size equal to or larger than Y. This makes it possible to satisfy the simultaneous recording / playback condition.
[0080]
In FIG. 3, recording areas 13, 14, and 15 are allocated as areas for recording real-time data A. Each of the recording areas 13 to 15 has a size equal to or larger than Y. Position information of the recording areas 13 to 15 is stored in the allocation area memory 507.
[0081]
The data recording means 505 instructs the optical disc drive 531 to record the real-time data A stored in the recording buffer memory 510 on the optical disc, and transfers the real-time data A to be recorded to the optical disc drive 531 (step S603). .
[0082]
In FIG. 3, real-time data A is recorded in a part of the recording area 13 in the recording operation W1. If it is determined in step S605 to be described later that the recording operation is to be continued, real-time data A is recorded from the beginning of the recording area 14 in the recording operation W2 after the access operation A1.
[0083]
3 shows an example in which the real-time data A is recorded from the middle of the recording area 13. However, when recording is started from the recording area 13, the real-time data A is recorded from the beginning of the recording area 13. You may make it do.
[0084]
When the user inputs an instruction to end recording or reproduction to the information recording / reproducing apparatus using the input unit 532, the recording / reproducing switching unit 502 ends the recording operation or the reproducing operation (step S604).
[0085]
The recording / reproducing switching unit 502 determines whether or not the recording buffer memory 510 is empty. If it is determined that the recording buffer memory 510 is empty, the recording operation of the real time data A is reproduced. When it is determined that the recording buffer memory 510 is not empty, the recording operation of the real-time data A is continued (step S605).
[0086]
In FIG. 3, since the recording buffer memory 510 becomes empty in the recording operation W2, switching from the recording operation of the real-time data A to the reproducing operation of the real-time data B occurs. As a result, after the access operation A2, the real time data B is read from a part of the reproduction area 17 in the reproduction operation R1. The reason for reproducing from the middle of the reproduction area is that the reproduction order has been changed by the editing process.
[0087]
Note that playback may be started from the beginning of the playback area 17. In this case, since the size of the reproduction area 17 is Y or more, the access operation A3 to the reproduction area 16 does not occur, and the recording operation is switched.
[0088]
The data reproduction means 506 instructs the optical disk drive 531 to reproduce the real-time data B from the optical disk, and transfers the real-time data B to be reproduced to the reproduction buffer memory 511 (step S606).
[0089]
The recording / playback switching unit 502 determines whether or not the playback buffer memory 511 is full. If it is determined that the playback buffer memory 511 is full, the playback operation of the real-time data B is changed to the real-time data A. When it is determined that the reproduction buffer memory 511 is not full, the reproduction operation of the real-time data B is continued (step S607).
[0090]
In FIG. 3, since the reproduction buffer memory 511 is full in the reproduction operation R2, switching from the reproduction operation of the real-time data B to the recording operation of the real-time data A occurs. As a result, after the access operation A4, the real time data A is recorded in the remaining area of the recording area 14 in the recording operation W3.
[0091]
When the recording of all data is completed, the file structure processing unit 504 records a file entry in the file structure area 12 in order to manage the area where the real time data is recorded as a real time extent ( Step S608).
[0092]
In this way, the recording operation of the real-time data A and the reproduction operation of the real-time data B can be switched while checking the storage state of the data in the recording buffer memory and the reproduction buffer memory.
[0093]
When simultaneously recording and reproducing n pieces of real-time data, a pickup P that accesses an area on the information recording medium, an encoding module EMi that encodes real-time data Di, and an encoded real-time data A recording buffer WBi for accumulating data Di, a reproduction buffer RBj for accumulating real-time data Dj read from the information recording medium, and a decoding module DMj for decoding the real-time data Dj accumulated in the reproduction buffer RBj Is used (hereinafter referred to as “n-simultaneous recording / reproducing model”). In this case, what is necessary is just to perform the following operation | movement in each step mentioned above.
[0094]
Step S602: The unallocated area search means 503 searches for an unallocated area in the volume space on the information recording medium, and allocates at least one unallocated area in the volume space as an area Ai for recording real-time data Di. .
[0095]
Step S603: The optical disc drive 531 executes a recording operation Wi for recording the real-time data Di accumulated in the recording buffer WBi in the area Ai in accordance with a recording instruction from the data recording means 505.
[0096]
Step S605: The recording / playback switching unit 502 determines whether or not the recording buffer WBi is empty while the recording operation Wi is being executed. If it is determined that the recording buffer WBi is empty, the recording operation is performed. Wi is switched to another recording operation Wi or reproduction operation Rj, and when it is determined that the recording buffer WBi is not empty, the recording operation Wi is continued.
[0097]
Step S606: The optical disk drive 531 executes a reproduction operation Rj for reading out the real-time data Dj from the area Aj in which the real-time data Dj is recorded in accordance with the reproduction instruction from the data reproduction means 506.
[0098]
Step S607: The recording / reproducing switching unit 502 determines whether or not the reproduction buffer RBj is full while the reproduction operation Rj is being executed. If it is determined that the reproduction buffer RBj is full, the reproduction operation is performed. Rj is switched to another reproduction operation Rj or recording operation Wi, and when it is determined that the reproduction buffer RBj is not full, the reproduction operation Rj is continued.
[0099]
FIG. 6 shows a method for simultaneously recording and reproducing two pieces of real-time data. Thus, it has been described that the recording operation and the reproducing operation are alternately switched. However, when simultaneously recording and reproducing n pieces of real-time data, n may be an odd number, and the number of real-time data to be recorded and the number of real-time data to be reproduced may be different. For this reason, the recording operation may be switched to another recording operation, or the reproducing operation may be switched to another reproducing operation.
[0100]
Here, each of at least one area allocated as the area Ai is configured to satisfy the condition that the recording buffer WBi can be made empty by at most one access operation and at most two recording operations. Has been. Each of the at least one area allocated as the area Aj is configured to satisfy the condition that the reproduction buffer RBj can be full by at most one access operation and at most two reproduction operations. ing. Satisfying both of these two conditions satisfies the simultaneous recording / playback condition.
[0101]
For example, each of the at least one area allocated as the area Ai has a size equal to or larger than Y, and each of the at least one area allocated as the area Aj has a size equal to or larger than Y, Satisfy the requirements for recording and playback. The method for obtaining the minimum size Y of the recording area and the reproduction area is as described with reference to FIG.
[0102]
Y = 2 × n × Ta × Vd × Vt ÷ (Vt−n × Vd)
Ta represents an access time required for the pickup P to access between the innermost area and the outermost area of the information recording medium.
[0103]
Vt indicates a data transfer rate between the pickup P and the recording buffer WBi and a data transfer rate between the pickup P and the reproduction buffer RBj.
[0104]
Vd indicates the data transfer rate between the encoding module EMi and the recording buffer WBi and the data transfer rate between the decoding module DMj and the reproduction buffer RBj for all i and j.
[0105]
Note that i is an arbitrary integer of 1 to m, j is an arbitrary integer of m + 1 to n, m is an arbitrary integer of 1 or more that satisfies m <n, and n is simultaneously recorded and reproduced. It is an arbitrary integer of 2 or more indicating the number of the plurality of real-time data.
[0106]
Note that skip recording may be performed on a previously allocated area. Skip recording is a method of recording while avoiding defective sectors detected in advance or defective sectors detected during data recording. For example, in FIG. 8 showing the operation of skip recording, it is assumed that no defective sector is detected in the area 40 before recording, and defective areas 41, 42, and 43 are detected during recording. In this case, in order to record while avoiding the defective area, the data to be recorded in the defective area is recorded in the area next to the defective area. In the example of FIG. 8, data is recorded in the order of skip recording SW1, SW2, SW3, SW4. Skip recording may be performed while avoiding an area including a defective area not in units of sectors but in units of ECC blocks because the access time is short. Assuming that the size of the ECC block is E, the access time of the ECC block in skip recording in units of ECC blocks is E ÷ Vt. In the simultaneous recording / reproducing, in order to ensure compatibility between devices, the number of ECC blocks to be skipped may be limited. For example, let e be the ratio of areas that can be skipped in skip recording. In the simultaneous recording / reproducing condition shown in FIG. 1, when skip recording is applied, the minimum size of the recording area is set to Ye, and recording or reproduction is performed in the area of Ye × (1-e), and Ye × e. Since these areas are skipped, only access is performed. The condition for simultaneous recording / playback considering skip recording when the ratio is within a specific ratio is Ye × (1−e) ÷ Vt × (Vt−Vd) −Ta × Vd−Ye × e ÷ Vt × Vd = (3 XTa + Ye * (1-e) / Vt) * Vd + Ye * e / Vt * Vd, and Ye = 4 * Ta * Vd * Vt / (Vt-e * Vt-2 * Vd). The buffer size Be required in this case is Be = (4 × Ta + Ye × (1−e) ÷ Vt) × Vd + 2 × Ye × e / Vt × Vd.
[0107]
Note that recording in units of ECC blocks may be performed instead of recording in units of sectors.
[0108]
Although not shown in the drawing, a predetermined threshold value in the buffer is determined as a value for determining that the buffer is empty, and if it falls below this value, it is determined that the buffer is empty. It is determined that the buffer is full, and if this value is exceeded, it is determined that the buffer is full.For this reason, the buffer memory size is the minimum read, write unit margin, or rotation waiting time. You may have a margin.
[0109]
Since recording and reproduction are switched at the optimum timing, even when an error occurs during recording and reproduction and recording and reproduction cannot be performed for a certain period, the steady state is quickly drawn.
[0110]
2 is a model, and an encoder and a decoder are not necessarily required. A system that handles only a digital signal such as a streamer does not have an encoder or a decoder. However, by applying the present invention to a streamer, it is possible to transfer AV data without interruption.
[0111]
(Embodiment 2)
An embodiment in which real-time data transfer rates are different will be described. In the first embodiment, the simultaneous recording / playback conditions have been described on the assumption that the transfer rates are the same. In the present embodiment, by defining simultaneous recording / playback conditions for data having a high transfer rate and data having a low transfer rate, data having a low transfer rate can be recorded even in a small continuous free space. Memory can be made small.
[0112]
FIG. 9 shows two real-time data recording operations, reproducing operations and access operations for reproducing real-time data A having a high transfer rate and recording real-time data B having a low transfer rate. The simultaneous recording / reproducing model is the same as that shown in FIG. 2 described in the first embodiment. Since the transition of the data amount in the recording buffer and the reproduction buffer during the simultaneous recording / reproducing operation has been described in the first embodiment, it is omitted.
[0113]
FIG. 10 shows the layout of the recording area and the reproduction area on the disc, with the left side representing the inner circumference side of the disc and the right side representing the outer circumference side of the disc. In FIG. 10, playback areas 111, 112, and 113 are areas allocated as areas where real-time data A is recorded, and recording areas 114, 115, and 116 are allocated as areas where real-time data B is recorded. Area. The real-time data A is actually reproduced from the reproduction area 111 portion 101, the reproduction area 112 portions 102 and 103, and the reproduction area 113 104. Real-time data B is actually recorded in the portion 105 of the recording area 114, the portions 106 and 107 of the recording area 115, and the portion 108 of the recording area 116.
[0114]
In FIG. 9, A21 to A27 indicate an operation (access operation) of moving between areas to be accessed by the pickup 74. The time required for the access operations A21 to A27 is the time required for the pickup 74 to access between the innermost area and the outermost area of the disc (that is, the maximum access time Ta). Suppose there is. The data transfer rate between the recording buffer 72, the reproduction buffer 73, and the pickup 74 is assumed to be a constant Vt. The data transfer rate between the encoder 70 and the recording buffer 72 is Vd1 which is the maximum value of the variable rate, and the data transfer rate between the decoder 71 and the reproduction buffer 73 is Vd2 which is the maximum value of the variable rate. Suppose that
[0115]
In the reproduction operation R21, real-time data A is read from the area 101. After the access operation A21, the real-time data A is read from the area 102 in the reproduction operation R22. Thereafter, switching from the reproduction operation of the real-time data A to the recording operation of the real-time data B occurs (access operation A22).
[0116]
In the recording operation W21, the real time data B is recorded in the area 105. After the access operation A23, the real-time data B is recorded in the area 106 in the recording operation W22. Thereafter, switching from the recording operation of the real-time data B to the reproducing operation of the real-time data A occurs (access operation A24).
[0117]
As described above, the simultaneous recording / reproducing method of the present invention switches from the recording operation to the reproduction operation by at most one access operation and at most two recording operations, and at most one access. It is designed to satisfy the simultaneous recording / reproducing condition that the switching from the reproduction operation to the recording operation occurs by the operation and at most two reproduction operations.
[0118]
In the reproduction operation of the real time data A, the data in the reproduction buffer 73 is accumulated at Vt−Vd1, and the data in the reproduction buffer 73 is consumed at Vd1 in the access operation and the recording operation of the real time data B. The amount of data in the reproduction buffer 73 accumulated during the reproduction operation R21, the access operation A21, and the reproduction operation R22 is consumed between the access operation A22, the recording operation W21, the access operation A23, the recording operation W22, and the access operation A24. The amount of data in the reproduction buffer 73 is equal. Therefore, if the minimum size of at least one playback area allocated as the area where the real-time data A is recorded is Y1, and the minimum size of at least one recording area allocated as the area where the real-time data B is recorded is Y2. The following equation holds.
[0119]
Y1 ÷ Vt × (Vt−Vd1) = (4Ta + Y2 ÷ Vt) × Vd1
Y2 ÷ Vt × (Vt−Vd2) = (4Ta + Y1 ÷ Vt) × Vd2
By transforming this formula, the formula of the minimum size Y1 of the reproduction area and the minimum size Y2 of the recording area can be obtained.
[0120]
Y1 = (4Ta × Vt × Vd1) ÷ (Vt−Vd1−Vd2)
Y2 = (4Ta × Vt × Vd2) ÷ (Vt−Vd1−Vd2)
Each of at least one playback area assigned as an area where real-time data A is recorded has a size equal to or greater than Y1 and at least one recording area assigned as an area where real-time data B is recorded Having a size equal to or larger than Y2 can satisfy the simultaneous recording / reproducing condition for recording and reproducing two real-time data having different data transfer rates without omission.
[0121]
The buffer size B1 required for the reproduction buffer 73 and the buffer size B2 required for the recording buffer 72 are obtained according to the following equations.
[0122]
B1 = (4Ta + Y2 ÷ Vt) Vd1
B2 = (4Ta + Y1 ÷ Vt) Vd2
Thus, if Vd1> Vd2, Y2 and B2 can be made smaller than Y1 and B1, respectively.
[0123]
When real-time data A is recorded for the first time so that simultaneous recording / reproduction of real-time data is possible, if the maximum transfer rate of the data to be recorded / reproduced is known in advance, it will be larger than the size that satisfies the above simultaneous recording / reproduction conditions. Data can be recorded by allocating the free area to the recording area.
[0124]
As described above, in the recording / reproducing method described with reference to FIG. 6 of the first embodiment, the simultaneous recording / reproducing of the present embodiment can be performed by changing the simultaneous recording / reproducing condition expression in the search for the unallocated area.
[0125]
If the transfer rate is not known until immediately before recording, the real-time data A to be recorded first is the maximum transfer rate, and the transfer rate of real-time data B to be recorded while reproducing the real-time data A in the future is determined by the system. As the maximum value allowed, when recording real-time data A, the recording area can be searched to satisfy the simultaneous recording / playback condition. When the real-time data B data is recorded, the transfer rate is known, so that a recording area of the optimum size can be searched.
[0126]
The configuration of the information recording / reproducing apparatus is the same as that described in the first embodiment except for the size of the recording buffer memory and the reproduction buffer memory. The algorithm for switching between the recording operation and the reproduction operation is the same as that described in the first embodiment. That is, when the recording buffer memory becomes empty, the recording operation is switched to the reproducing operation, and when the reproducing buffer memory becomes full, the reproducing operation is switched to the recording operation.
[0127]
The present invention can also be applied to the case where audio data is additionally recorded later on AV data compressed by MPEG. By setting in advance a transfer rate of audio data to be dubbed later, the minimum size of the reproduction area of MPEG data can be obtained. In the case of post-recording, audio data can be recorded at an appropriate timing while reproducing already recorded MPEG data.
[0128]
Further, as will be described below, the number of audio data to be dubbed can be made two by increasing the number of real-time data and determining the conditions for simultaneous recording / playback. For example, recording can be performed first with MPEG data, and BGM and narration can be recorded independently.
[0129]
FIG. 11 shows three real-time data recording operations, reproducing operations, and access operations with different data transfer rates. Similarly to FIG. 9, R31 to R38 are reproduction operations, W31 to W42 are recording operations, A31 to A40 are access operations, 121 to 128 are portions of a reproduction area where real-time data is actually read, and 129 to 132 are real-time operations. A portion of a recording area where data is actually recorded is shown. Based on FIG. 11, as in the case of simultaneously recording / reproducing two real-time data, the condition for simultaneously recording / reproducing three real-time data is obtained.
Y1 = (6Ta × Vt × Vd1) ÷ (Vt−Vd1−Vd2−Vd3)
Y2 = (6Ta × Vt × Vd2) ÷ (Vt−Vd1−Vd2−Vd3)
Y3 = (6Ta × Vt × Vd3) ÷ (Vt−Vd1−Vd2−Vd3)
B1 = (6Ta + Y2 ÷ Vt + Y3 ÷ Vt) Vd1
B2 = (6Ta + Y3 ÷ Vt + Y1 ÷ Vt) Vd2
B3 = (6Ta + Y1 ÷ Vt + Y2 ÷ Vt) Vd3
It becomes. Here, Y, Vd, and B indicate the minimum size of the reproduction area or recording area, the transfer rate of data to be reproduced or recorded, and the buffer size of the reproduction buffer or recording buffer, respectively, and the subscripts indicate the real-time Indicates the data number.
[0130]
Furthermore, when simultaneously recording / reproducing n pieces of real-time data, the above-described “n-simultaneous recording / reproducing model” is used. The minimum size Yi of each of the at least one recording area allocated as the area Ai for recording the real-time data Di, the size Bi of the recording buffer WBi for storing the real-time data Di, and the area for recording the real-time data Dj The minimum size Yj of each of the at least one reproduction area allocated as Aj and the size Bj of the reproduction buffer WBj for accumulating real-time data Dj are obtained according to the following formula.
[0131]
Yi = (2 × n × Ta × Vt × Vdi) ÷ {Vt− (Vd1 + Vd2 +... + Vdn)},
Yj = (2 × n × Ta × Vt × Vdj) ÷ {Vt− (Vd1 + Vd2 +... + Vdn)},
Bi = {2 × n × Ta + (Y1 + Y2 +... + Yn) ÷ Vt−Yi ÷ Vt) Vdi
Bj = {2 × n × Ta + (Y1 + Y2 +... + Yn) ÷ Vt−Yj ÷ Vt) Vdj
Ta represents an access time required for the pickup P to access between the innermost area and the outermost area of the information recording medium.
[0132]
Vt indicates a data transfer rate between the pickup P and the recording buffer WBi and a data transfer rate between the pickup P and the reproduction buffer RBj.
[0133]
Vdi indicates a data transfer rate between the encoding module EMi and the recording buffer WBi.
[0134]
Vdj represents a data transfer rate between the decoding module DMj and the reproduction buffer RBj.
[0135]
Note that i is an arbitrary integer of 1 to m, j is an arbitrary integer of m + 1 to n, m is an arbitrary integer of 1 or more that satisfies m <n, and n is simultaneously recorded and reproduced. It is an arbitrary integer of 2 or more indicating the number of the plurality of real-time data.
[0136]
The above simultaneous recording / playback conditions can also be applied when the transfer rates of the respective real-time data are the same (that is, when Vd1 = Vd2 =... = Vdn).
[0137]
(Embodiment 3)
A description will be given of an embodiment in which real-time data transfer rates are different and real-time data is simultaneously recorded and reproduced at a fixed transfer rate. DV format data used in digital video cameras has a fixed transfer rate, not variable rate data as in MPEG. In the case of real-time data at a fixed rate, if the optimum recording / playback area size can be determined, the playback operation and recording operation can be switched in units of recording / playback areas, and the switching operation can be simplified and recording / playback can be performed. The size of the area can be reduced.
[0138]
FIG. 28 is a diagram showing a layout of a recording area in which two real-time data are simultaneously recorded and reproduced. As shown in the figure, the size of each recording area is recorded at a fixed size that differs for each type of data to be recorded.
[0139]
FIG. 12 shows a recording operation, a reproducing operation, and an access operation of two real-time data having different data transfer rates. Similarly to FIG. 9, R51 to R52 indicate playback operations, W51 to W52 indicate recording operations, A51 to A53 indicate access operations, 151 to 152 indicate playback areas, and 153 to 154 indicate recording areas. Since the rate is fixed, switching between the reproduction operation and the recording operation can be performed in units of areas. Therefore, the playback operation can be switched to the recording operation when the playback from one playback area is completed, and the recording operation can be switched to the playback operation when the recording into one recording area is completed.
[0140]
The configuration of the information recording / reproducing apparatus is the same as that of the information recording / reproducing apparatus shown in FIG. 5 except that the operation of the unallocated area searching unit 503 and the operation of the recording / reproducing switching unit 502 are different.
[0141]
FIG. 27 shows the procedure of the simultaneous recording / playback method. Such a method can be stored in a memory in the system control unit 501 in the form of a program, for example. Such a program can be executed by a microcomputer in the system control unit 501, for example.
[0142]
The simultaneous recording / playback procedure shown in FIG. 27 differs in the simultaneous recording / playback conditional expression in the unallocated area search step (S701) and the condition (S702, S703) for switching between the recording operation and the playback operation. Is the same as the simultaneous recording / playback procedure shown in the first embodiment (FIG. 6).
[0143]
In step S701, the unallocated area search unit 503 searches for an unallocated area having a size of Y1 (or Y2), and records real-time data B for at least one unallocated area searched in this way. Assign as an area. A method for obtaining the size Y1 (or Y2) of the recording area will be described later.
[0144]
In step S702, the recording / reproducing switching unit 502 determines whether or not the real-time data B has been recorded up to the end of at least one recording area allocated as an area for recording the real-time data B in the recording operation of the real-time data B. If it is determined that the real-time data B has been recorded up to the end of the recording area, the recording operation of the real-time data B is switched to the reproduction operation of the real-time data A. If it is determined that the end of the recording area has not been recorded, the real-time data B recording operation is continued.
[0145]
In step S703, the recording / playback switching unit 502 reads the real-time data A up to the end of at least one playback area allocated as the area where the real-time data A is recorded in the playback operation of the real-time data A. If it is determined that the real-time data A has been read up to the end of the recording area, the reproduction operation of the real-time data A is switched to the recording operation of the real-time data B, and the real-time data When it is determined that A has not been read to the end of the recording area, the reproduction operation of the real-time data A is continued.
[0146]
The data amount of the reproduction buffer 73 accumulated during the reproduction operation R51 is equal to the data amount of the reproduction buffer 73 consumed during the access operation A51, the recording operation W51, and the access operation A52. Accordingly, when the size of at least one reproduction area allocated as an area where the real-time data A is recorded is Y1, and the size of at least one recording area allocated as an area where the real-time data B is recorded is Y2, The following equation holds.
[0147]
Y1 ÷ Vt × (Vt−Vd1) = (2Ta + Y2 ÷ Vt) × Vd1
Y2 ÷ Vt × (Vt−Vd2) = (2Ta + Y1 ÷ Vt) × Vd2
By transforming this formula, the formula of the reproduction area size Y1 and the recording area size Y2 is obtained.
[0148]
Y1 = (2Ta × Vt × Vd1) ÷ (Vt−Vd1−Vd2)
Y2 = (2Ta × Vt × Vd2) ÷ (Vt−Vd1−Vd2)
The buffer size B1 required for the reproduction buffer 73 and the buffer size B2 required for the recording buffer 72 are obtained according to the following equations.
[0149]
B1 = (2Ta + Y2 ÷ Vt) Vd1
B2 = (2Ta + Y1 ÷ Vt) Vd2
In this way, by utilizing the fact that the recording rate is different, by setting the simultaneous recording / playback conditions for fixed-rate real-time data, real-time data is recorded in a smaller recording area for low-rate data. It becomes possible, and the free space on the disk can be used effectively.
[0150]
Further, considering the case where three real-time data are simultaneously recorded / reproduced with the same consideration, FIG. 13 shows a recording operation, a reproduction operation, and an access operation.
Y1 = (3Ta × Vt × Vd1) ÷ (Vt−Vd1−Vd2−Vd3)
Y2 = (3Ta × Vt × Vd2) ÷ (Vt−Vd1−Vd2−Vd3)
Y3 = (3Ta × Vt × Vd3) ÷ (Vt−Vd1−Vd2−Vd3)
B1 = (3Ta + Y2 ÷ Vt + Y3 ÷ Vt) Vd1
B2 = (3Ta + Y3 ÷ Vt + Y1 ÷ Vt) Vd2
B3 = (3Ta + Y1 ÷ Vt + Y2 ÷ Vt) Vd3
It becomes.
[0151]
Furthermore, when simultaneously recording / reproducing n pieces of real-time data, the above-described “n-simultaneous recording / reproducing model” is used. In this case, the following operations may be performed in steps S701, S603, S606, S702, and S703 shown in FIG.
[0152]
Step S701: The unallocated area search means 503 searches for an unallocated area in the volume space on the information recording medium, and allocates at least one unallocated area in the volume space as an area Ai for recording real-time data Di.
[0153]
Step S603: The optical disc drive 531 executes a recording operation Wi for recording the real-time data Di accumulated in the recording buffer WBi in the area Ai in accordance with a recording instruction from the data recording means 505.
[0154]
Step S702: The recording / reproducing switching means 502 determines whether or not the real-time data Di has been recorded up to one end of at least one recording area allocated as the area Ai in the recording operation Wi. When it is determined that the data Di has been recorded up to the end of the recording area, the recording operation Wi is switched to another recording operation Wi or the reproduction operation Wj, and the real-time data Di is not recorded up to the end of the recording area. If it is determined, the recording operation Wi is continued.
[0155]
Step S606: The optical disk drive 531 executes a reproduction operation Rj for reading out the real-time data Dj from the area Aj in which the real-time data Dj is recorded in accordance with the reproduction instruction from the data reproduction means 506.
[0156]
Step S703: The recording / reproducing switching means 502 determines whether or not the real-time data Dj has been read up to one end of at least one reproduction area allocated as the area Aj in the reproduction operation Rj. If it is determined that the data Dj has been read up to the end of the playback area, the playback operation Rj is switched to another playback operation Rj or recording operation Wi, and the real-time data Dj is read out to the end of the playback area If it is determined that it has not been performed, the reproduction operation Wj is continued.
[0157]
FIG. 27 shows a method for simultaneously recording and reproducing two pieces of real-time data. Thus, it has been described that the recording operation and the reproducing operation are switched alternately. However, in the case of simultaneously recording and reproducing n pieces of real-time data, n may be an odd number, and the number of real-time data to be recorded and the number of real-time data to be reproduced may be different. For this reason, the recording operation may be switched to another recording operation, or the reproducing operation may be switched to another reproducing operation.
[0158]
Here, each of the at least one area allocated as the area Ai includes n access operations, (m−1) recording operations, and (nm) times of switching between the recording operation and the reproduction operation. The real-time data Di accumulated in the recording buffer WBi during the reproduction operation is configured to satisfy the condition that it can be recorded by one recording operation, and the at least one allocated as the area Aj Each of the areas has n access operations and (n−m−1) reproductions associated with switching between the reproduction operation and the recording operation of the real-time data Dj stored in the reproduction buffer RBj during one reproduction operation. It is configured to satisfy the condition that it can be consumed between the operation and the m recording operations. Satisfying both of these two conditions satisfies the simultaneous recording / playback condition.
[0159]
For example, each of at least one recording area allocated as the area Ai for recording the real-time data Di has a size of Yi, and at least one reproduction allocated as the area Ai for reproducing the real-time data Dj Since each of the areas has a size of Yj, the simultaneous recording / reproducing condition can be satisfied.
[0160]
The size Yi of the recording area, the size Yj of the reproduction area, the size Bi of the recording buffer WBi, and the size Bj of the reproduction buffer RBj are obtained according to the following equations.
[0161]
Yi = (n × Ta × Vt × Vdi) ÷ {Vt− (Vd1 + Vd2 +... + Vdn)}
Yj = (n × Ta × Vt × Vdj) ÷ {Vt− (Vd1 + Vd2 +... + Vdn)}
Bi = {n × Ta + (Y1 + Y2 +... + Yn) ÷ Vt−Yi ÷ Vt} Vdi
Bj = {n × Ta + (Y1 + Y2 +... + Yn) ÷ Vt−Yj ÷ Vt} Vdj
Ta represents an access time required for the pickup P to access between the innermost area and the outermost area of the information recording medium.
[0162]
Vt indicates a data transfer rate between the pickup P and the recording buffer WBi and a data transfer rate between the pickup P and the reproduction buffer RBj.
[0163]
Vdi indicates a data transfer rate between the encoding module EMi and the recording buffer WBi.
[0164]
Vdj represents a data transfer rate between the decoding module DMj and the reproduction buffer RBj.
[0165]
Note that i is an arbitrary integer of 1 to m, j is an arbitrary integer of m + 1 to n, m is an arbitrary integer of 1 or more that satisfies m <n, and n is simultaneously recorded and reproduced. It is an arbitrary integer of 2 or more indicating the number of the plurality of real-time data.
[0166]
Next, the access performance of a drive for recording / reproducing a disc will be described. FIG. 14 is a diagram showing a breakdown of the access time of the drive when accessing the sector of the target track. When the access distance is large, the pick-up moves and access time takes as much as the rough seek. When recording data, in the CLV system (constant linear velocity system) disk, the rotation speed of the disk must be changed depending on the radial position to be accessed. Therefore, the rotation of the spindle motor that rotates the disk is accelerated or decelerated. A spindle lock time is required to adjust to a predetermined rotational speed. Since the address search becomes possible when the number of revolutions of the disk is locked, it takes an access time equivalent to a fine seek to access a target track by performing a multi-jump in a plurality of tracks by mainly using a pickup optical system. After that, recording or reproduction can be performed by waiting for rotation until a predetermined sector comes. If the access distance is within the range of the fine seek, the access time will be the fine seek and rotation waiting time. If the access is 1/3 of the disk capacity, the spindle lock time and coarse seek time will be the access time. I can do it.
[0167]
As described above, by determining the access performance of the drive in advance, the access time between the extents in simultaneous recording / playback can be the access time required from the access performance of the drive, not the full seek. As a result, a value smaller than the full seek time can be used in the simultaneous recording / playback condition, so that recording can be performed in a smaller continuous recording area. In addition, there are more cases where it is possible to determine that continuous playback is possible even when the extent becomes shorter during editing.
[0168]
FIG. 26 is a diagram illustrating the layout and layout of the recording area at the time of simultaneous recording of three real-time data. For example, if the recording area 128 and the recording area 129 are separated from each other by the distance between the area on the innermost side of the disc and the area on the outermost circumference, the time required for the access operations A40, A34, and A36 is the full seek access. If the recording area 122 and the recording area 121 are about 100 tracks apart, the time required for the access operation A31 is almost equal to the fine seek access time.
[0169]
In the simultaneous recording / reproducing method shown in FIG. 6, the estimation of the access time (first access time or second access time) is performed in the unallocated area search step S602. In the simultaneous recording / reproducing method shown in FIG. 27, the access time is estimated in the unallocated area search step S701. The access time is estimated by the unallocated area search means 503 (FIG. 5).
[0170]
Therefore, the simultaneous recording / reproducing conditions described in the second embodiment are as follows, considering the estimation of the access time.
[0171]
Yi = {2 × (T1 +... + Tn) × Vt × Vdi} ÷ {Vt− (Vd1 + Vd2 +... + Vdn)}
Yj = {2 × (T1 +... + Tn) × Vt × Vdj} ÷ {Vt− (Vd1 + Vd2 +... + Vdn)}
Bi = {2 × (T1 +... + Tn) + (Y1 + Y2 +... + Yn) ÷ Vt−Yi ÷ Vt} Vdi
Bj = {2 × (T1 +... + Tn) + (Y1 + Y2 +... + Yn) ÷ Vt−Yj ÷ Vt} Vdj
Here, Tk indicates the first access time or the second access time. The first access time is an access time required for the pickup P to access the area Al from the area Ak. The second access time refers to an access time required to access another one from at least one area assigned as the area Ak. k and l are arbitrary integers from 1 to n, and k ≠ l.
[0172]
Note that i is an arbitrary integer of 1 to m, j is an arbitrary integer of m + 1 to n, m is an arbitrary integer of 1 or more that satisfies m <n, and n is simultaneously recorded and reproduced. It is an arbitrary integer of 2 or more indicating the number of the plurality of real-time data.
[0173]
The above simultaneous recording / playback conditions can also be applied when the transfer rates of the respective real-time data are the same (that is, when Vd1 = Vd2 =... = Vdn).
[0174]
In addition, the simultaneous recording / reproducing conditions described in the third embodiment are as follows in consideration of the estimation of the access time.
[0175]
Yi = {(T1 +... + Tn) × Vt × Vdi} ÷ {Vt− (Vd1 + Vd2 +... + Vdn)}
Yj = {(T1 +... + Tn) * Vt * Vdj} / {Vt- (Vd1 + Vd2 + ... + Vdn)}
Bi = {(T1 +... + Tn) + (Y1 + Y2 +... + Yn) / Vt-Yi / Vt} Vdi
Bj = {(T1 +... + Tn) + (Y1 + Y2 +... + Yn) / Vt-Yj / Vt} Vdj
Here, Tk indicates an access time required for the pickup P to access the area Al from the area Ak. k and l are arbitrary integers from 1 to n, and k ≠ l.
[0176]
Note that i is an arbitrary integer of 1 to m, j is an arbitrary integer of m + 1 to n, m is an arbitrary integer of 1 or more that satisfies m <n, and n is simultaneously recorded and reproduced. It is an arbitrary integer of 2 or more indicating the number of the plurality of real-time data.
[0177]
The above simultaneous recording / playback conditions can also be applied when the transfer rates of the respective real-time data are the same (that is, when Vd1 = Vd2 =... = Vdn).
[0178]
Next, a method for improving the disk utilization efficiency and editability by limiting the full seek time will be described. FIG. 15 is a diagram showing the relationship between the rotational speed difference of the spindle motor of the drive and the access time,
TRQ = (N1-N2) .J / (dt.Kj)
Assuming that the access time Tacc is
Tacc = (spindle lock time) + (rotation waiting time) + constant
= (N1-N2) * J / (TRQ * KJ) + Trev + constant
≒ A × dN + B
Here, A, B: constant, dN: rotation speed difference (= N1-N2), dt: spindle lock time, J: disk inertia, Kj: conversion constant, N1: rotation speed before access, N2: after access , Trev: rotation waiting time, TRQ: motor torque, and an access performance model is set from the relationship between the disk rotation speed difference and the access time. As described with reference to FIG. 14, when the pickup is moved to the vicinity of the target track, it is necessary to change the rotational speed of the coarse seek and the spindle motor. In the performance of the spindle motor used in the optical disk drive, the access time is dominated by changes in the spindle rotation speed. Thus, paying attention to the fact that the spindle lock time is proportional to the difference in the rotation speed, the access time can be formulated as described above. Further, when the rotation waiting time Trev is sufficiently smaller than the spindle lock time, it can be omitted, and the access time Tacc can be estimated linearly with respect to the disc rotation speed difference dN.
[0179]
Further, if the initial position and the target position of the pickup are known, the rotational speed of the disk and the rotational speed difference can be uniquely obtained from the relationship with the linear velocity of the disk.
If the address before access is A1, the address after access is A2, the radius positions are r1 and r2, respectively, and the radius position at the location where the address is 0 is r0, the address is proportional to the band-like area. So, let C be a constant,
A1 = C · (π · r1 · r1−π · r0 · r0)
A2 = C · (π · r2 · r2-π · r0 · r0)
Since the rotational speed at a certain address is inversely proportional to the radius, the rotational speeds of A1 and A2 are defined as N1, N2, and D as constants.
N1 = D / r1
N2 = D / r2
Therefore, by using the above relational expression, the rotational speed can be obtained from the address.
[0180]
FIG. 16 is a diagram showing the relationship between the radial position of the disk and the rotational speed, and shows an example of a disk having a diameter of 12 cm, a capacity of 25 GB, and a read rate of 72 Mbps. Since the product of the radial position and the rotational speed is constant, when accessing with the same distance in the radial direction, the access time is shortened because the rotational speed difference is smaller on the outer peripheral side than on the inner peripheral side. The volume space is an area with a radius of 24 mm to 58 mm, and the full seek time is proportional to the rotational speed difference 2270 rpm. If the AV data recording area is an area having a radius of 38 mm to 58 mm, the access time is proportional to the rotational speed difference of 840 rpm, and therefore is about 2.7. As shown in FIG. 29, when the worst access time in the area from the radius of 24 mm to 58 mm is 1000 msec, the worst access time is 370 msec if the recording area is provided in the range from the radius of 38 mm to 58 mm. Note that the capacity of the area from the radius 38 mm to 58 mm is reduced by about 30% to 17 GB, and if the demand for capacity is not strong, the AV data recording area is set on the outer peripheral side as a high-speed access zone, so that the access time Can be significantly reduced, and the size of the necessary continuous recording area under the simultaneous recording / reproducing conditions can be reduced in proportion to this. Therefore, when performing post-recording, chasing playback, etc., setting a high-speed access zone increases the number of cases where simultaneous recording / playback can be performed continuously even if the extent becomes shorter.
[0181]
When recording using the above characteristics, the recording may be classified into a disk set with a high-speed access zone and a disk not set. Information indicating which class is class 1 when the high-speed access zone is set and class 0 when not, may be recorded in the lead-in area or the volume space. In addition, the maximum access time in the high-speed access zone may be further recorded together with class information. In this way, even if the disc is inserted into a different device, information about the class can be known, so that compatibility between devices is improved.
[0182]
In addition, when a 25 GB optical disk is used in a consumer video recorder such as a VTR, the recording time can be as long as 10 hours. It will be possible to do with this disc. In such a case, it is possible to ensure editing performance after recording by setting a plurality of high-speed access zones.
[0183]
Also, in a two-layer disc, zones are provided on each surface so that the radial positions are the same on the recording surfaces of the first layer and the second layer, and a high-speed access zone composed of these two zones is set. Thus, by providing a high-speed access zone in a single-layer disc, capacity reduction becomes a problem, but in a dual-layer disc, this is solved. Note that the radial positions of the recording surfaces of the first and second layers have a physical intersection, and therefore cannot be set to the exact same radial position. Since the time to access by switching the focus switching time and rotation waiting time of the pickup is generally smaller than the fine seek, the switching time between layers is the time to access between the innermost to the outermost in the high-speed access zone. Small enough for it.
[0184]
When simultaneously recording and reproducing n pieces of real-time data, the area Ai for recording the real-time data Di and the area Aj for reproducing the real-time data Dj for all i and j are arranged on the outer periphery of the information recording medium. (E.g., in a high-speed access zone). Thereby, the access time can be shortened.
[0185]
(Embodiment 4)
In the first, second, and third embodiments, basic contents of the invention for realizing simultaneous recording / playback have been described. In the present embodiment, an example in which simultaneous recording / playback is actually applied using three specific examples of post-recording will be described. The after-recording method described in this embodiment describes a method for recording a new audio data by recognizing a place where new audio data is recorded while reproducing pre-recorded video data and audio data, and recording the new audio over the original audio. Yes. When audio data and video data are not recorded as one MPEG stream, but are recorded in different areas, the audio data and video data are regarded as two real-time data. Simultaneous recording can be performed using the method described in the first, second, and third embodiments.
[0186]
17, 18 and 19 will be described with respect to a recording method and a reproducing method when performing post-recording on a disc on which data encoded by mixing audio data and video data is recorded. Note that audio data to be recorded during post-recording is recorded in a recording area secured in advance. In this example, data encoded by mixing audio data and video data such as MPEG data and DV data is referred to as AVM (Audio Video Mix Data). FIG. 17 is a diagram showing an arrangement of AVM data and post-recording data on a disk. A recording area for audio data for after-recording is secured at predetermined intervals so that after-recording is possible (recording areas 180, 182, 184, 190, and 192). The recording areas 181, 183, 185, 187, 189, and 191 indicate areas where AVM data is recorded. The subscripts of AVM indicate the order of data, with the subscripts indicated by AVM0 to AVMp + 3.
[0187]
In post-recording, audio data is recorded while reproducing AVM data. Since the reproduction of AVM data is performed by once accumulating data in the buffer, the pickup needs to read the data from the disk in advance. For this reason, audio data for post-recording cannot be recorded immediately after the AVM data. In the present invention, an after-recording recording area is secured in front of the AVM data recording area so that the buffer during reproduction is reduced. In this way, the reproduction can be started immediately after the audio is read out and then the video is read out, so that the size of the reproduction buffer can be reduced. In the case of reading out the video first, it is not possible to start playback until the data is read out once and the reading of the audio data is started. The reason for starting reading from audio data instead of starting from video data is that the time until image output is possible is shortened. Since the AVM data has a higher data rate than the audio data for after-recording, when the recording area for the AVM data is read first, the image cannot be output unless the recording area for after-recording is accessed. Conversely, if audio data is read out, an after-recording recording area with a small data size is read out, and an image can be output after accessing the AVM recording area.
[0188]
The playback start position is set in the recording area 181, the audio and video after-recording start positions are set in the recording areas 182 and 183, respectively. The after-recording end positions are set in the recording areas 190 and 191, and the playback ends. The position is set in the recording area 193.
[0189]
FIG. 18 shows the order of access during post-recording with respect to the recording area described in FIG. At the time of recording, since it is difficult in terms of timing to record data in an after-recording recording area set in front after reading the AVM, there is a feature in that corresponding after-recording data is recorded retroactively by 1 AVM. For example, after AVM2 is played back, dubbing data corresponding to AVM1 is recorded in a recording area set before AVM1 by going back 1 AVM. As described above, after the AVM is read out, the audio data for after-recording corresponding to the different AVM that has been read out is recorded, so that simultaneous recording / playback can be performed.
[0190]
Here, P is the number of continuous areas that are continuously read in a complete form (P> = 0), and Tpr1AV indicates the net time for reading AVM0 from the playback start position. The meaning of P repetitions indicates that, for example, when P = 3, A2, AVM2, A3, AVM3, A4, and AVM4 exist in the range of P repetitions. As described above with respect to skip recording, if there are a defective ECC blocks in the recording area of AVM0, the time for reading one ECC block is Ts, and a × Ts is required in addition to Tpr1AV. Tf1, Tf2, Tfj, and Tfj are access times between the recording areas, and indicate accesses in the range of about the fine seek. Tpr2AV is the time to read the dubbing start position in the recording area of AVM1, TinAV is the time to read from the dubbing start position to the end of the AVM1 recording area, and ToutAV is to the end position of the dubbing in the AVM recording area The time for reading is shown. TcA is the net time for reading the audio recording area for post-recording, TcAV is the net time for reading the recording area for AVM, TinA is the time for reading data from the post-recording start position in the recording area for post-recording, and ToutA is This shows the time for reading data to the post-recording end position in the post-recording recording area. Tpo1AV is a time for reading data after the after-recording end position in the recording area where the after-recording end position is set. Tpo2AV indicates a time for reading data up to the reproduction end position in the recording area where the reproduction end position is set. Here, a and b respectively indicate the number of ECC blocks to be skipped in the AVM recording area and the after-recording recording area.
[0191]
Consider a condition for simultaneous recording / playback whether or not post-recording is possible in the illustrated access order. If the data size of the real-time data recorded on the disc is larger than the product of the time from the start of reading the data until the next recording area of the data is accessed and the data rate of the data, playback is possible. The buffer is never empty. From this,
Y / Vd => Tpr1AV + Tf1 + TcAV + Tf2 + TcAV + 2 * Tfj + TinA + (P-1) * (TcAV + TcA + 2 * Tfj) + TcAV + 2 * Tfj + TcA + Tpo2AV + (P + 1) * (a + b) * Ts + 3 *
Also,
Y = (Tpr1AV + (P + 2) * TcAV + Tpo2AV) * Vt
TinAV * Vt * (VdA / Vd) = TinA * Vt, ToutAV * Vt * (VdA / Vd) = ToutA * Vt,
TcAV * Vt * (VdA / Vd) = TcA * Vt, TcAV = Tpr2AV + TinAV = ToutAV + Tpo1AV
Here, Y is the AVM data size recorded in the section from the start of playback to the end of playback in FIG. 17, Vd is the transfer rate between the decoding module and the playback buffer for AVM, and VdA is The transfer rate between the encoding module and the recording buffer for audio data for post-recording, Vt is the data transfer rate at which the pickup P reads data from the disc.
Therefore,
Y / Vd => (Tf1 + Tf2 + (P + 1) * 2 * Tfj + (P + 1) * (a + b) * Ts + 3 * a * Ts− (Tpr1AV + Tpr2AV + ToutAV + Tpo1AV + Tpo2AV) * VdA / Vd) * Vt− (Vd−Vd−Vd−VdV).
Also, consider one cycle of after-recording until the AVM is read, the after-recording audio recording area is accessed, the after-recording audio is recorded, and the next AVM recording area is accessed.
Y '/ Vd => TcAV + 2 * Tfj + TcA + (a + b) * Ts
Y '= TcAV * Vt
Here, Y ′ is the size of one AVM recording area, for example, the size of the area 187.
Therefore,
Y ′ / Vd => (2 * Tfj + (a + b) * Ts) * Vt / (Vt−Vd−VdA)
In addition, since the reproduction start position is set in the middle of the recording area 181, in order to consider this influence, considering from the reproduction start to Tf2,
Y ″ / Vd => Tpr1AV + Tf1 + TcAV + Tf2 + 2 * a * Ts
Y ″ = (Tpr1AV + TcAV) * Vt
Therefore,
Y ″ / Vd => (Tf1 + Tf2 + 2 * a * Ts) * Vt / (Vt−Vd)
And if all of the above equations are satisfied, it can be said that dubbing is possible.
[0192]
If the expression indicated by Y ′ / Vd on the left side is not satisfied, it can be seen that simultaneous recording / playback cannot be performed within a range of P repetitions. In this way, in order to check in which access it becomes impossible to perform simultaneous recording and reproduction, an expression is set for each predetermined section.
[0193]
FIG. 19 shows an access order when data reproduction is confirmed after dubbing. At the time of reproduction, since the data for after-recording is in front of the recording area of the AVM, the data can be read without access. The audio and video playback conditions are
YV / VdV => Tpr1AV + Tf1 + TinA + TcAV + P * (TcAV + TcA) + ToutA + Tf2 + TcAV + Tf3 + Tpo2AV + (P + 2) * (a + b) * Ts + 2 * a * Ts
YV = (Tpr1AV + (P + 2) * TcAV + Tpo2AV) * Vt * (VdV / Vd)
YA / VdA => Tpr1AV + Tf1 + TinA + TcAV + P * (TcAV + TcA) + ToutA + Tf2 + TcAV + Tf3 + Tpo2AV + (P + 2) * (a + b) * Ts + 2 * a * Ts
YA = (Tpr1AV + Tpr2AV + Tpo1AV + Tpo2AV) * Vt * (VdA / Vd) + (TinA + P * TcA + ToutA) * Vt
TinAV * Vt * (VdA / Vd) = TinA * Vt,
ToutAV * Vt * (VdA / Vd) = ToutA * Vt
TcAV * Vt * (VdA / Vd) = TcA * Vt
TcAV = Tpr2AV + TinAV = ToutAV + Tpo1AV
Therefore,
YV / VdV => (Tf1 + Tf2 + Tf3 + (P + 2) * (a + b) * Ts + 2 * a * Ts− (Tpr1AV + Tpr2AV + Tpo1AV + TpoAV2) * VdA / Vd) * Vt / (Vt−VdA)
The video playback conditions are as follows: reading audio data for dubbing and reading AVM are one dubbing cycle.
YV '/ VdV => TcA + TcAV + (a + b) * Ts
YV '= TcAV * Vt * (VdV / Vd)
Therefore,
Y ′ / Vd => ((a + b) * Ts) * Vt / (Vt−Vd−VdA)
It is looser than the recording conditions.
[0194]
Next, as a second example, a recording method and a reproducing method in the case where audio data to be recorded at the time of post-recording is recorded in another recording area separated from the AVM data will be described with reference to FIGS.
[0195]
FIG. 20 is a diagram showing the arrangement of AVM data and post-recording data on a disk. AVM data is continuously recorded (recording areas 200, 201, 202, 203, 204, 205), and post-recording data is recorded in a separate area from the AVM data (recording areas 206, 207, 208, 209).
[0196]
The playback start position is set in the recording area 200, the audio and video after-recording start positions are set in the recording areas 201 and 206, respectively, and the after-recording end position is set in the recording areas 204 and 209, and the playback end. The position is set in the recording area 205.
[0197]
FIG. 21 shows the order of access during post-recording with respect to the recording area described in FIG. At the time of recording, as described above, there is a feature in that corresponding post-record data is recorded as far back as 1 AVM. In the previous description, since the recording area for AVM data and the recording area for post-recording were arranged close to each other, the access time between these areas was small. In this case, however, the recording area becomes large and the size of the necessary recording area is large. Become. However, there is a degree of freedom in the arrangement of the recording area for post-recording. For this reason, it is possible to record new post-recording data in a new area while overwriting old data without overwriting the recorded post-recording data.
[0198]
Consider a condition for simultaneous recording / playback whether or not post-recording is possible in the illustrated access order.
[0199]
Here, Ta1, Ta2, Tai, and Taj are subscripts of i and j, indicating the access time between the areas determined from the access performance of the drive, and indicating access close to the full seek area.
The video conditions for simultaneous recording and playback during dubbing are as follows:
Y / Vd => Tpr1AV + 2 * TcAV + Ta1 + TinA + (P-1) * (TcAV + TcA + Taj + Tai) + Ta2 + TcAV + Ta3 + TcA + Ta4 + Tpo2AV + (P + 1) * (a + b) * Ts + 3 * a * Ts
Y = (Tpr1AV + (P + 2) * TcAV + Tpo2AV) * Vt
TinAV * Vt * (VdA / Vd) = TinA * Vt
ToutAV * Vt * (VdA / Vd) = ToutA * Vt
TcAV * Vt * (VdA / Vd) = TcA * Vt
TcAV = Tpr2AV + TinAV = ToutAV + Tpo1AV
Here, the meaning of P iterations in FIG. 21 is 2 <= j = <P. For example, when P = 3, AVM2, A1, AVM3, A2, AVM4, and A3 exist in the range of P iterations. It shows what to do.
Therefore,
Y / Vd => Ta1 + Ta2 + (P-1) * (Taj + Tai) + Ta3 + Ta4 + (P + 1) * (a + b) * Ts + 3 * a * Ts- (Tpr1AV + Tpr2AV + ToutAV + Tpo1AV + Tpo2AV) * VdA / Vd) * Vt / (Vt) * Vd / (Vt)
Considering one cycle of post-recording, assuming that reading of AVMj + 1, access to Aj, recording of Aj, and access to AVMj + 2 are one cycle,
Y ′ / Vd => TcAV + Taj + TcA + Tai + (a + b) * Ts
Y '= TcAV * Vt
Therefore,
Y ′ / Vd => (Taj + Tai + (a + b) * Ts) * Vt / (Vt−Vd−VdA)
Furthermore, considering the range from the playback start position to Tai,
Y ″ / Vd => Tpr1AV + 2 * TcAV + Ta1 + TinA + Tai + 3 * a * Ts + b * Ts
Y ″ = (Tpr1AV + 2 * TcAV) * Vt
Therefore,
Y ″ / Vd => (Ta1 + TinA + Tai + 3 * a * Ts + b * Ts) * Vt / (Vt−Vd)
If all three conditional expressions whose left side is Y / Vd, Y ′ / Vd, and Y ″ / Vd are satisfied, after-recording is possible.
[0200]
FIG. 22 shows the order of access when data reproduction is confirmed after dubbing. During playback, access occurs because the data for post-recording is separated from the recording area of the AVM.
The condition of the video at the time of dubbing is
YV / VdV => (Tpr1AV + Ta1 + TinA + Ta2 + TcV + P * (TcA + Taj + TcAV + Taj) + Ta3 + ToutA + Ta4 + TcAV + Tpo2AV + (P + 2) * (a + b) * Ts + 2 * a * Ts)
YV = (Tpr1AV + Tpr2AV + TinAV + P * TcAV + TcAV + Tpo2AV) * Vt * (VdV / Vd)
Also, audio conditions when playing dubbing data
YA / VdA => (Tpr1AV + Ta1 + TinA + Ta2 + TcV + P * (TcA + Taj + TcAV + Taj) + Ta3 + ToutA + Ta4 + TcAV + Tpo2AV + (P + 2) * (a + b) * Ts + 2 * a * Ts)
YA = (Tpr1AV + Tpr2AV + Tpo1AV + Tpo2AV) * Vt * (VdA / Vd) + (TinA + P * TcA + ToutA) * Vt
TinAV * Vt * (VdA / Vd) = TinA * Vt
ToutAV * Vt * (VdA / Vd) = ToutA * Vt
TcAV * Vt * (VdA / Vd) = TcA * Vt
TcAV = Tpr2AV + TinAV = ToutAV + Tpo1AV
Therefore,
YV / VdV => (Ta1 + Ta2 + 2 * P * Taj + Ta3 + Ta4 + (P + 2) * (a + b) * Ts + 2 * a * Ts- (Tpr1AV + Tpr2AV + ToutAV + Tpo1AV + Tpo2AV) * VdA / Vd) * Vt / (Vt-d)
Also, the conditions regarding video in the range from the playback start position to Ta2 are
(Tpr1AV * Vt * (VdV / Vd)) / VdV => (Tpr1AV + Ta1 + TinA + Ta2 + (a + b) * Ts)
Therefore,
(Tpr1AV * Vt * (VdV / Vd)) / VdV => (TinAV + Ta1 + Ta2 + (a + b) * Ts) * Vt / (Vt−Vd)
Also, the video conditions from pre-roll to just before A & Vj are:
YV '/ VdV => (Tpr1AV + Ta1 + TinA + Ta2 + TcAV + Taj + TcA + Taj + 2 * (a + b) * Ts)
YV '= (Tpr1AV + TcAV) * Vt * (VdV / Vd)
Therefore,
YV ′ / VdV => (Ta1 + Ta2 + 2 * Taj + 2 * (a + b) * Ts + TinA−Tpr1A) * Vt / (Vt−Vd−VdA)
It becomes.
[0201]
The difference from recording is that the corresponding audio data is read and then the AVM is read. However, comparing one dubbing cycle with one cycle reading Aj and AVMj, only Taj is different. If all are the same, the conditions are the same.
[0202]
Next, as a third example, a recording method in which audio data and video data are encoded and recorded in different areas, and audio data to be recorded at the time of post-recording is also recorded in another recording area separated from the video data. The playback method will be described with reference to FIGS.
[0203]
FIG. 23 is a diagram showing the arrangement of video data, audio data, and post-record data on a disc. Video data and audio data are recorded alternately in different areas at a predetermined cycle. (Recording areas for video data are 210, 212, 214, 216, 218, 220, recording areas for audio data are 211, 213, 215, 217, 219, 221), and post-recording data is separated from these data. (Recording areas 222, 223, 224, and 225).
[0204]
The audio and video playback start positions are set in the recording areas 211 and 210, the audio and video after-recording start positions are set in the recording areas 213 and 212, respectively, and the after-recording end positions are set in the recording areas 219 and 212, respectively. The playback end positions are set in the recording areas 221 and 220, respectively. Further, the after-recording start and end positions of the after-recording data are set in the recording areas 222 and 225.
[0205]
In this way, at the time of post-recording recording, from the recording area 210 to 211 is read from the start of playback to the end of playback, and new audio data is added to the audio data Ai from the start to the end of post-recording to create a new Recorded in areas 222-225. In this case, simultaneous recording / playback of recording audio data for post-recording is performed while reproducing two pieces of real-time data, which are already recorded audio data and video data.
[0206]
FIG. 24 shows the order of access during post-recording and the read time from the recording area or the recording time or access time to the recording area for the recording area described in FIG. At the time of recording, as described above, there is a feature in that the corresponding post-record data is recorded by going back one video data. In the previous description, since video data and audio data were recorded as AVM data, there was no access between the video data and audio data. However, in this example, access is necessary because they are recorded independently. However, there is a degree of freedom in the arrangement of audio data recording areas. For this reason, audio data can be recorded in a new area while overwriting old data without overwriting the audio data. Similarly, there is an advantage that data for dubbing can be newly recorded many times.
[0207]
Consider a condition for simultaneous recording / playback whether or not post-recording is possible in the illustrated access order.
The video conditions for simultaneous recording and playback during dubbing are as follows:
YV / VdV => Tpr1A + Tpr1V + Tf1 + 2 * (TcA + TcV + 2Tfj) + 2 * Taj + TinA + (P-1) * (TcV + 2 * TcA + Tfj + 2 * Taj) + TcA + Tfj + Tc + Tc + Tp + Tc + Tp + Tc + Tp + Tp + Tc + Tp
Here, the meaning of P iterations in FIG. 24 is 2 <= j = <P. For example, in the case of P = 3, A2, V2, B1, A3, V3, B2, A4 are within the range of P iterations. , V4, and B3 are present.
YV = (Tpr1V + (P + 2) * TcV + Tpo2V) * Vt
TinV * VdA = TinA * VdV
ToutV * VdA = ToutA * VdV
TcV * VdA = TcA * VdV
TcV = Tpr2V + TinV = ToutV + Tpo1V
TcA = Tpr2A + TinA = ToutA + Tpo1A
Therefore,
YV / VdV => (Tf1 + Tf2 + (P + 5) * Tfj + (2 * P + 2) Taj + (P + 1) * (a + b) * Ts + 3 * a * Ts-Tpr1A-Tpri2A-ToutA-Tpo1A-Tpo2A) * Vt / -Vt-Vd 2 * VdA)
Considering one cycle of post-recording, one cycle consists of reading Aj + 1, accessing Vj + 1, reading Vj + 1, accessing Bj, recording Bj, and accessing the next Aj + 2.
YV '/ VdV => TcA + Tfj + TcV + 2 * Taj + TcA + (a + 2 * b) * Ts
YV '= TcV * Vt
Therefore, Y ′ / Vd => (Tfj + 2 * Taj + (a + 2 * b) * Ts) * Vt / (Vt−VdV−2 * VdA)
Furthermore, considering the range from the playback start position to immediately before Vj + 1,
YV ″ / VdV => Tpr1A + Tpr1V + Tf1 + 2 * (TcA + TcV + 2Tfj) + 2 * Taj + TinA + TcA + Tfj + 3 * a * Ts + 5 * b * Ts
YV ″ = (Tpr1V + 2 * TcV) * Vt
Therefore, YV ″ / Vd => (TinA + TcA + 2 * Taj + Tf1 + 5 * Tfj + 3 * a * Ts + 5 * b * Ts) * Vt / (Vt−VdV−VdA)
Thus, simultaneous recording / playback can be performed by determining the size of each recording area of audio data, video data, and post-recording data in a size that satisfies the above three conditional expressions.
[0208]
The post-recording data has been described as an example in which the audio data is recorded in a separate area from the video data. However, the video data, audio data, post-recording data are recorded in advance so as to secure the area when recording the video data. The recording areas may be alternately arranged in the order of the use data. In this case, since the area is secured in advance, it is difficult to use for other purposes without post-recording, but the access time to post-recording data is shortened, so the conditions for simultaneous recording and playback are relaxed. The
[0209]
FIG. 25 shows an access order when data reproduction is confirmed after dubbing. In recording, it is necessary to record Bj after reading Aj. However, in the reproduction confirmation, access to Aj and reading of Aj are not necessary, and the recording conditions are looser.
[0210]
【The invention's effect】
  The present inventionAccording toIn order to switch the switching timing between recording and playback according to the amount of data stored in the buffer memory, the recording buffer is controlled to remain nearly empty, and the playback buffer is controlled to remain nearly full. The For this reason, even if a state occurs in which data cannot be read from the pickup for a predetermined period, simultaneous recording / playback can be performed stably. Since the switching timing of recording and playback is appropriately switched, simultaneous recording / playback can be realized with a small buffer memory. In addition, by allocating data so that the area in which data is recorded exceeds the minimum size considering four accesses, simultaneous recording / playback is ensured even for discs recorded by other devices. Can do.
[0211]
In addition, by setting the optimum simultaneous recording / playback conditions using the difference in the transfer rate of the data to be recorded and played back, it becomes possible to record data with a low transfer rate in a smaller recording area, and the use efficiency of the disk increases. .
[Brief description of the drawings]
FIG. 1 is a diagram showing conditions for simultaneous recording / playback in an information recording medium according to Embodiment 1 of the present invention;
FIG. 2 is a diagram showing a model for realizing simultaneous recording / playback
FIG. 3 is a layout diagram showing access on a disc in the information recording medium of Embodiment 1 of the present invention;
FIG. 4 is a diagram showing a simultaneous recording / reproducing switching operation in the information recording medium according to the first embodiment of the present invention;
FIG. 5 is a block diagram showing a configuration of an information recording / reproducing apparatus according to Embodiment 1 of the present invention.
FIG. 6 is a flowchart showing a simultaneous recording / playback method according to the first embodiment of the present invention.
FIG. 7 is a diagram showing a directory structure of recorded data
FIG. 8 is a diagram showing an operation of skip recording.
FIG. 9 is a diagram showing recording / reproduction and access operations during simultaneous recording / reproduction of two real-time data according to the second embodiment of the present invention;
FIG. 10 is a diagram showing a layout of a reproduction area and a recording area on a disc according to the second embodiment of the present invention.
FIG. 11 is a diagram showing recording / reproduction and access operations at the time of simultaneous recording / reproducing of three real-time data according to the second embodiment of the present invention;
FIG. 12 is a diagram showing recording / reproduction and access operations during simultaneous recording / reproduction of two real-time data according to the third embodiment of the present invention;
FIG. 13 is a diagram showing recording / reproduction and access operations during simultaneous recording / reproduction of three real-time data according to the third embodiment of the present invention;
FIG. 14 shows a breakdown of access time according to the third embodiment of the present invention.
FIG. 15 is a diagram showing the relationship between the disc rotation speed difference and the access time according to the third embodiment of the present invention.
FIG. 16 is a diagram showing the relationship between the radial position of the disk and the difference in rotational speed according to the third embodiment of the present invention.
FIG. 17 is a diagram showing an arrangement of recording areas when AVM data and after-recording data are alternately recorded according to the fourth embodiment of the present invention;
FIG. 18 is a diagram showing a recording / reproducing access operation during post-recording when AVM data and post-recording data are alternately recorded according to the fourth embodiment of the present invention;
FIG. 19 is a diagram showing a reproduction access operation after post-recording when AVM data and post-recording data are alternately recorded according to the fourth embodiment of the present invention;
FIG. 20 is a diagram showing an arrangement of recording areas when AVM data and post-recording data are recorded separately according to the fourth embodiment of the present invention.
FIG. 21 is a diagram showing a recording / reproducing access operation during post-recording when AVM data and post-recording data are recorded separately according to the fourth embodiment of the present invention;
FIG. 22 is a diagram showing a reproduction access operation after post-recording when AVM data and post-recording data according to Embodiment 4 of the present invention are recorded separately.
FIG. 23 is a diagram showing an arrangement of recording areas when audio data, video data, and post-record data are recorded in different areas according to the fourth embodiment of the present invention.
FIG. 24 is a diagram showing a recording / playback access operation during post-recording when audio data, video data, and post-recording data are recorded in different areas according to the fourth embodiment of the present invention;
FIG. 25 is a diagram showing a reproduction access operation after post-recording when audio data, video data, and post-recording data are recorded in different areas according to the fourth embodiment of the present invention;
FIG. 26 is a diagram showing access and recording area layout when simultaneously recording three real-time data according to the third embodiment of the present invention;
FIG. 27 is a flowchart showing a simultaneous recording / playback method according to the third embodiment of the present invention;
FIG. 28 is a diagram showing a layout of a recording area for performing simultaneous recording / playback of two real-time data according to the third embodiment of the present invention.
FIG. 29 is a diagram showing an access area on a disk and an access time required for a full seek in the area according to the third embodiment of the present invention.
FIG. 30 is a diagram showing the conditions for conventional simultaneous recording / playback;
FIG. 31 is a diagram showing a conventional simultaneous recording / playback operation;

Claims (11)

A method of simultaneously recording and reproducing a plurality of real-time data on an information recording medium according to a simultaneous recording and reproducing model,
The simultaneous recording / reproducing model includes a pickup P that accesses an area on the information recording medium, an encoding module EMi that encodes real-time data Di, and a recording buffer WBi that stores encoded real-time data Di. A reproduction buffer RBj for accumulating the real-time data Dj read from the information recording medium, and a decoding module DMj for decoding the real-time data Dj accumulated in the reproduction buffer RBj,
The method
A first step of searching an unallocated area in the volume space on the information recording medium and allocating at least one unallocated area in the volume space as an area Ai for recording real-time data Di;
A second step of executing a recording operation Wi for recording the real-time data Di accumulated in the recording buffer WBi in the area Ai;
A third step of executing a reproduction operation Rj for reading out the real-time data Dj from the area Aj in which the real-time data Dj is recorded;
While executing the recording operation Wi, it is determined whether or not the recording buffer WBi is empty. If it is determined that the recording buffer WBi is empty, the recording operation Wi is changed to another recording operation or reproducing operation Rj. And when it is determined that the recording buffer WBi is not empty, a fourth step of continuing the recording operation Wi;
While the reproduction operation Rj is being executed, it is determined whether or not the reproduction buffer RBj is full. If it is determined that the reproduction buffer RBj is full, the reproduction operation Rj is changed to another reproduction operation or recording operation Wi. And when it is determined that the reproduction buffer RBj is not full, a fifth step of continuing the reproduction operation Rj;
Including
At least one of the recorded real-time data Di and reproduced real-time data Dj includes data encoded at a variable rate;
Each of the at least one area allocated as the area Ai is configured to satisfy the condition that the recording buffer WBi can be made empty by the access operation at most and the recording operation at most twice. And
Each of the at least one area allocated as the area Aj is configured to satisfy the condition that the reproduction buffer RBj can be full by at most one access operation and at most two reproduction operations. And
Here, i is an arbitrary integer of 1 to m, j is an arbitrary integer of m + 1 to n, m is an arbitrary integer of 1 or more that satisfies m <n, and n is simultaneous recording / playback. 2 or more arbitrary integer der indicating the number of the plurality of real-time data to be is,
When the data rate of the real-time data Di is maximum, the minimum size of the area allocated as the area Ai is a real-time value that includes one access operation and two recording operations in the second to fifth steps. Data amount of recording buffer WBi consumed when data Di recording operation is executed, and data stored in recording buffer WBi when real time data Dj reproducing operation including other access operation and reproducing operation is executed Based on the quantity,
Method. When the data rate of the real-time data Di is maximum, the minimum size of the area allocated as the area Ai is a real-time value that includes one access operation and two recording operations in the second to fifth steps. Data amount of recording buffer WBi consumed when data Di recording operation is executed, and data stored in recording buffer WBi when real time data Dj reproducing operation including other access operation and reproducing operation is executed The method of claim 1, wherein the amount is determined to be equal . If you want to re-simultaneous recording of two of the real-time data, the second to fifth step, the first recording operation, the first access operation, the second recording operation, the second access operation, the first playback operation, the third access The real-time data Di recording operation is composed of the first recording operation, the first access operation, and the second recording operation, and the real-time data Dj reproducing operation is performed in the order of the operation, the second reproduction operation, and the fourth access operation. The method according to claim 2, comprising a second access operation, a first reproduction operation, a third access operation, a second reproduction operation, and a fourth access operation . Each of the at least one region allocated as the region Ai has a size equal to or larger than Y, and each of the at least one region allocated as the region Aj has a size equal to or larger than Y,
here,
Y = 2 × n × Ta × Vd × Vt ÷ (Vt−n × Vd),
Ta represents an access time required for the pickup P to access between the innermost area and the outermost area of the information recording medium,
Vt represents a data transfer rate between the pickup P and the recording buffer WBi and a data transfer rate between the pickup P and the reproduction buffer RBj,
Vd indicates a data transfer rate between the encoding module EMi and the recording buffer WBi and a data transfer rate between the decoding module DMj and the reproduction buffer RBj for all i and j . 4. The method according to any one of 3 . Each of the at least one region allocated as the region Ai has a size equal to or greater than Yi, and each of the at least one region allocated as the region Aj has a size equal to or greater than Yj,
here,
Yi = (2 × n × Ta × Vt × Vdi) ÷ {Vt− (Vd1 + Vd2 +... + Vdn)},
Yj = (2.times.n.times.Ta.times.Vt.times.Vdj) / {Vt- (Vd1 + Vd2 +. The access time required to access between
Vt represents a data transfer rate between the pickup P and the recording buffer WBi and a data transfer rate between the pickup P and the reproduction buffer RBj,
Vdi indicates the data transfer rate between the encoding module EMi and the recording buffer WBi,
The method according to claim 1, wherein Vdj indicates a data transfer rate between the decoding module DMj and the reproduction buffer RBj. Area Ai and the area Aj, all i, with respect to j, provided in a region from the radius 38mm of the information recording medium to 58 mm, A method according to any one of claims 1 to 5. An information recording / reproducing apparatus for simultaneously recording / reproducing a plurality of real-time data on an information recording medium according to a simultaneous recording / reproducing model,
The simultaneous recording / reproducing model includes a pickup P that accesses an area on the information recording medium, an encoding module EMi that encodes real-time data Di, and a recording buffer WBi that stores encoded real-time data Di. A reproduction buffer RBj for accumulating the real-time data Dj read from the information recording medium, and a decoding module DMj for decoding the real-time data Dj accumulated in the reproduction buffer RBj,
The information recording / reproducing apparatus comprises:
First means for searching an unallocated area in the volume space on the information recording medium and allocating at least one unallocated area in the volume space as an area Ai for recording real-time data Di;
A second means for executing a recording operation Wi for recording the real-time data Di accumulated in the recording buffer WBi in the area Ai;
A third means for executing a reproduction operation Rj for reading out the real-time data Dj from the area Aj in which the real-time data Dj is recorded;
While executing the recording operation Wi, it is determined whether or not the recording buffer WBi is empty. If it is determined that the recording buffer WBi is empty, the recording operation Wi is changed to another recording operation Wi or a reproducing operation. Switching to Rj, and when it is determined that the recording buffer WBi is not empty, a fourth means for continuing the recording operation Wi;
While the reproduction operation Rj is being executed, it is determined whether or not the reproduction buffer RBj is full. If it is determined that the reproduction buffer RBj is full, the reproduction operation Rj is changed to another reproduction operation Rj or recording operation. Switching to Wi, and when it is determined that the reproduction buffer RBj is not full, a fifth means for continuing the reproduction operation Rj, and
At least one of the recorded real-time data and the reproduced real-time data includes data encoded at a variable rate;
Each of the at least one area allocated as the area Ai is configured to satisfy the condition that the recording buffer WBi can be made empty by at most one access operation and at most two recording operations. ,
Each of the at least one area allocated as the area Aj is configured to satisfy the condition that the reproduction buffer RBj can be full by at most one access operation and at most two reproduction operations. ,
Here, i is an arbitrary integer of 1 to m, j is an arbitrary integer of m + 1 to n, m is an arbitrary integer of 1 or more that satisfies m <n, and n is simultaneous recording / playback. 2 or more arbitrary integer der indicating the number of the plurality of real-time data to be is,
The minimum size of the area allocated as the area Ai is when the data rate of the real-time data Di is maximum,
In the second to fifth means, the data amount of the recording buffer WBi consumed when a real-time data Di recording operation consisting of one access operation and two recording operations is executed, and other access operations Real-time data Dj including the reproduction operation is determined based on the amount of data stored in the recording buffer WBi when the reproduction operation is executed.
Information recording / reproducing apparatus. The minimum size of the area allocated as the area Ai is when the data rate of the real-time data Di is maximum,
In the second to fifth means, the data amount of the recording buffer WBi consumed when a real-time data Di recording operation consisting of one access operation and two recording operations is executed, and other access operations 8. The information recording / reproducing apparatus according to claim 7, wherein the amount of data stored in the recording buffer WBi when the real-time data Dj reproducing operation including the reproducing operation is executed is determined to be equal . When simultaneously recording and reproducing two real-time data, the second to fifth means are the first recording operation, the first access operation, the second recording operation, the second access operation, the first reproduction operation, and the third access operation. , The second reproduction operation and the fourth access operation are executed in order, the real-time data Di recording operation is composed of the first recording operation, the first access operation, and the second recording operation, and the real-time data Dj reproduction operation is the first recording operation. 9. The information recording / reproducing apparatus according to claim 8, comprising a two-access operation, a first reproduction operation, a third access operation, a second reproduction operation, and a fourth access operation . Each of the at least one region allocated as the region Ai has a size equal to or larger than Y, and each of the at least one region allocated as the region Aj has a size equal to or larger than Y,
here,
Y = 2 × n × Ta × Vd × Vt ÷ (Vt−n × Vd),
Ta represents an access time required for the pickup P to access between the innermost area and the outermost area of the information recording medium,
Vt represents a data transfer rate between the pickup P and the recording buffer WBi and a data transfer rate between the pickup P and the reproduction buffer RBj,
Vd indicates a data transfer rate between the encoding module EMi and the recording buffer WBi and a data transfer rate between the decoding module DMj and the reproduction buffer RBj for all i and j. The information recording / reproducing apparatus according to any one of claims 9 to 9 . Each of the at least one region allocated as the region Ai has a size equal to or greater than Yi, and each of the at least one region allocated as the region Aj has a size equal to or greater than Yj,
here,
Yi = (2 × n × Ta × Vt × Vdi) ÷ {Vt− (Vd1 + Vd2 +... + Vdn)},
Yj = (2.times.n.times.Ta.times.Vt.times.Vdj) / {Vt- (Vd1 + Vd2 +... + Vdn)}, Ta is the area where the pickup P is located on the innermost circumference and the outermost circumference of the information recording medium. The access time required to access
Vt represents a data transfer rate between the pickup P and the recording buffer WBi and a data transfer rate between the pickup P and the reproduction buffer RBj,
Vdi indicates the data transfer rate between the encoding module EMi and the recording buffer WBi,
10. The information recording / reproducing apparatus according to claim 7, wherein Vdj indicates a data transfer rate between the decoding module DMj and the reproduction buffer RBj .

Images